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JavaScript Practical Coding Challenges For Beginners
by CodeGuppyJuly 19th, 2020
Too Long; Didn't Read
JavaScript Practical Coding Challenges For Beginners. The challenges are intended for beginners, therefore the proposed solutions are implemented using only simple and classical programming elements. Each solution is accompanied by an online link that helps you quickly run it in a code playground at codeguppy.com. If you have time, we recommend you to solve the challenges on your own and then compare your solution to the provided solution. If time is limited, just browse through the solutions! The code is making use of the codegupp specific function.
Hello JavaScript code newbie! In this article I'm proposing you a series of coding challenges that will help you practice the basic language constructs and algorithms.
These coding challenges are intended for beginners, therefore the proposed solutions are implemented using only simple and classical programming elements. Each solution is accompanied by an online link that helps you quickly run it in a code playground at codeguppy.com
If you have time, we recommend you to solve the challenges on your own and then compare your solution to the provided solution. If time is limited, just browse through the solutions!
Note: The code is making use of the codeguppy specific function println() to print the results. If you want to run these solutions outside codeguppy.com, just replace println() with console.log() then run them using your browser console tool or node.js.
Coding challenge #1: Print numbers from 1 to 10
https://codeguppy.com/code.html?mrgCtLGA90Ozr0Otrs5Z
for(var i = 1; i <= 10; i++)
{
println(i);
}
Coding challenge #2: Print the odd numbers less than 100
https://codeguppy.com/code.html?eDLA5XPp3bPxP79H2jKT
for(var i = 1; i <= 100; i += 2)
{
println(i);
}
Coding challenge #3: Print the multiplication table with 7
https://codeguppy.com/code.html?fpnQzIhnGUUmCUZy1fyQ
for(var i = 1; i <= 10; i++)
{
var row = "7 * " + i + " = " + 7 * i;
println(row);
}
Coding challenge #4: Print all the multiplication tables with numbers from 1 to 10
https://codeguppy.com/code.html?78aD4mWSCzoNEVxOQ8tI
for(var i = 1; i <= 10; i++)
{
printTable(i);
println("");
}
function printTable(n)
{
for(var i = 1; i <= 10; i++)
{
var row = n + " * " + i + " = " + n * i;
println(row);
}
}
Coding challenge #5: Calculate the sum of numbers from 1 to 10
https://codeguppy.com/code.html?Vy6u9kki2hXM4YjsbpuN
var sum = 0;
for(var i = 1; i <= 10; i++)
{
sum += i;
}
println(sum);
Coding challenge #6: Calculate 10!
https://codeguppy.com/code.html?IIuJX4gnXOndNu0VrywA
var prod = 1;
for(var i = 1; i <= 10; i++)
{
prod *= i;
}
println(prod);
Coding challenge #7: Calculate the sum of odd numbers greater than 10 and less than 30
https://codeguppy.com/code.html?DcOffOyoIArmNZHVNM2u
var sum = 0;
for(var i = 11; i <= 30; i += 2)
{
sum += i;
}
println(sum);
Coding challenge #8: Create a function that will convert from Celsius to Fahrenheit
https://codeguppy.com/code.html?oI5mWm6QIMRjY1m9XAmI
function celsiusToFahrenheit(n)
{
return n * 1.8 + 32;
}
var r = celsiusToFahrenheit(20);
println(r);
Coding challenge #9: Create a function that will convert from Fahrenheit to Celsius
https://codeguppy.com/code.html?mhnf8DpPRqqgsBgbJNpz
function fahrenheitToCelsius(n)
{
return (n - 32) / 1.8;
}
var r = fahrenheitToCelsius(68);
println(r);
Coding challenge #10: Calculate the sum of numbers in an array of numbers
https://codeguppy.com/code.html?TteeVr0aj33ZyCLR685L
function sumArray(ar)
{
var sum = 0;
for(var i = 0; i < ar.length; i++)
{
sum += ar[i];
}
return sum;
}
var ar = [2, 3, -1, 5, 7, 9, 10, 15, 95];
var sum = sumArray(ar);
println(sum);
Coding challenge #11: Calculate the average of the numbers in an array of numbers
https://codeguppy.com/code.html?7i9sje6FuJsI44cuncLh
function averageArray(ar)
{
var n = ar.length;
var sum = 0;
for(var i = 0; i < n; i++)
{
sum += ar[i];
}
return sum / n;
}
var ar = [1, 3, 9, 15, 90];
var avg = averageArray(ar);
println("Average: ", avg);
Coding challenge #12: Create a function that receives an array of numbers and returns an array containing only the positive numbers
Solution 1:
https://codeguppy.com/code.html?0eztj1v6g7iQLzst3Id3
function getPositives(ar)
{
var ar2 = [];
for(var i = 0; i < ar.length; i++)
{
var el = ar[i];
if (el >= 0)
{
ar2.push(el);
}
}
return ar2;
}
var ar = [-5, 10, -3, 12, -9, 5, 90, 0, 1];
var ar2 = getPositives(ar);
println(ar2);
Coding challenge #12: Create a function that receives an array of numbers and returns an array containing only the positive numbers
Solution 2
https://codeguppy.com/code.html?KefrPtrvJeMpQyrB8V2D
function getPositives(ar)
{
var ar2 = [];
for(var el of ar)
{
if (el >= 0)
{
ar2.push(el);
}
}
return ar2;
}
var ar = [-5, 10, -3, 12, -9, 5, 90, 0, 1];
var ar2 = getPositives(ar);
println(ar2);
Coding challenge #12: Create a function that receives an array of numbers and returns an array containing only the positive numbers
Solution 3
https://codeguppy.com/code.html?qJBQubNA7z10n6pjYmB8
function getPositives(ar)
{
return ar.filter(el => el >= 0);
}
var ar = [-5, 10, -3, 12, -9, 5, 90, 0, 1];
var ar2 = getPositives(ar);
println(ar2);
Coding challenge #13: Find the maximum number in an array of numbers
https://codeguppy.com/code.html?THmQGgOMRUj6PSvEV8HD
function findMax(ar)
{
var max = ar[0];
for(var i = 0; i < ar.length; i++)
{
if (ar[i] > max)
{
max = ar[i];
}
}
return max;
}
var ar = [-5, 10, -3, 12, -9, 5, 90, 0, 1];
var max = findMax(ar);
println("Max: ", max);
Coding challenge #14: Print the first 10 Fibonacci numbers without recursion
https://codeguppy.com/code.html?rKOfPxHbVwxNWI2d8orH
var f0 = 0;
println(f0);
var f1 = 1;
println(f1);
for(var i = 2; i < 10; i++)
{
var fi = f1 + f0;
println(fi);
f0 = f1;
f1 = fi;
}
Coding challenge #15: Create a function that will find the nth Fibonacci number using recursion
https://codeguppy.com/code.html?IneuIg9O0rRV8V76omBk
function findFibonacci(n)
{
if (n == 0)
return 0;
if (n == 1)
return 1;
return findFibonacci(n - 1) + findFibonacci(n - 2);
}
var n = findFibonacci(10);
println(n);
Coding challenge #16: Create a function that will return a Boolean specifying if a number is prime
https://codeguppy.com/code.html?fRYsPEc2vcZTbIU8MKku
function isPrime(n)
{
if (n < 2)
return false;
if (n == 2)
return true;
var maxDiv = Math.sqrt(n);
for(var i = 2; i <= maxDiv; i++)
{
if (n % i == 0)
{
return false;
}
}
return true;
}
println(2, " is prime? ", isPrime(2));
println(3, " is prime? ", isPrime(3));
println(4, " is prime? ", isPrime(4));
println(5, " is prime? ", isPrime(5));
println(9, " is prime? ", isPrime(9));
Coding challenge #17: Calculate the sum of digits of a positive integer number
https://codeguppy.com/code.html?RHA714FYio8gWgmjWYPz
function sumDigits(n)
{
var s = n.toString();
var sum = 0;
for(var char of s)
{
var digit = parseInt(char);
sum += digit;
}
return sum;
}
var sum = sumDigits(1235231);
println("Sum: ", sum);
Coding challenge #18: Print the first 100 prime numbers
https://codeguppy.com/code.html?gnMVeOZXN6VhLekyvui8
printPrimes(100);
// Function prints the first nPrimes numbers
function printPrimes(nPrimes)
{
var n = 0;
var i = 2;
while(n < nPrimes)
{
if (isPrime(i))
{
println(n, " --> ", i);
n++;
}
i++;
}
}
// Returns true if a number is prime
function isPrime(n)
{
if (n < 2)
return false;
if (n == 2)
return true;
var maxDiv = Math.sqrt(n);
for(var i = 2; i <= maxDiv; i++)
{
if (n % i == 0)
{
return false;
}
}
return true;
}
Coding challenge #19: Create a function that will return in an array the first "nPrimes" prime numbers greater than a particular number "startAt"
https://codeguppy.com/code.html?mTi7EdKrviwIn4bfrmM7
println(getPrimes(10, 100));
function getPrimes(nPrimes, startAt)
{
var ar = [];
var i = startAt;
while(ar.length < nPrimes)
{
if (isPrime(i))
{
ar.push(i);
}
i++;
}
return ar;
}
// Returns true if a number is prime
function isPrime(n)
{
if (n < 2)
return false;
if (n == 2)
return true;
var maxDiv = Math.sqrt(n);
for(var i = 2; i <= maxDiv; i++)
{
if (n % i == 0)
{
return false;
}
}
return true;
}
Coding challenge #20: Rotate an array to the left 1 position
https://codeguppy.com/code.html?MRmfvuQdZpHn0k03hITn
var ar = [1, 2, 3];
rotateLeft(ar);
println(ar);
function rotateLeft(ar)
{
var first = ar.shift();
ar.push(first);
}
Coding challenge #21: Rotate an array to the right 1 position
https://codeguppy.com/code.html?fHfZqUmkAVUXKtRupmzZ
var ar = [1, 2, 3];
rotateRight(ar);
println(ar);
function rotateRight(ar)
{
var last = ar.pop();
ar.unshift(last);
}
Coding challenge #22: Reverse an array
https://codeguppy.com/code.html?GZddBqBVFlqYrsxi3Vbu
var ar = [1, 2, 3];
var ar2 = reverseArray(ar);
println(ar2);
function reverseArray(ar)
{
var ar2 = [];
for(var i = ar.length - 1; i >= 0; i--)
{
ar2.push(ar[i]);
}
return ar2;
}
Coding challenge #23: Reverse a string
https://codeguppy.com/code.html?pGpyBz0dWlsj7KR3WnFF
var s = reverseString("JavaScript");
println(s);
function reverseString(s)
{
var s2 = "";
for(var i = s.length - 1; i >= 0; i--)
{
var char = s[i];
s2 += char;
}
return s2;
}
Coding challenge #24: Create a function that will merge two arrays and return the result as a new array
https://codeguppy.com/code.html?vcTkLxYTAbIflqdUKivc
var ar1 = [1, 2, 3];
var ar2 = [4, 5, 6];
var ar = mergeArrays(ar1, ar2);
println(ar);
function mergeArrays(ar1, ar2)
{
var ar = [];
for(let el of ar1)
{
ar.push(el);
}
for(let el of ar2)
{
ar.push(el);
}
return ar;
}
Coding challenge #25: Create a function that will receive two arrays of numbers as arguments and return an array composed of all the numbers that are either in the first array or second array but not in both
https://codeguppy.com/code.html?Y9gRdgrl6PPt4QxVs7vf
var ar1 = [1, 2, 3, 10, 5, 3, 14];
var ar2 = [1, 4, 5, 6, 14];
var ar = mergeExclusive(ar1, ar2);
println(ar);
function mergeExclusive(ar1, ar2)
{
var ar = [];
for(let el of ar1)
{
if (!ar2.includes(el))
{
ar.push(el);
}
}
for(let el of ar2)
{
if (!ar1.includes(el))
{
ar.push(el);
}
}
return ar;
}
Coding challenge #26: Create a function that will receive two arrays and will return an array with elements that are in the first array but not in the second
https://codeguppy.com/code.html?bUduoyY6FfwV5nQGdXzH
var ar1 = [1, 2, 3, 10, 5, 3, 14];
var ar2 = [-1, 4, 5, 6, 14];
var ar = mergeLeft(ar1, ar2);
println(ar);
function mergeLeft(ar1, ar2)
{
var ar = [];
for(let el of ar1)
{
if (!ar2.includes(el))
{
ar.push(el);
}
}
return ar;
}
Coding challenge #27: Create a function that will receive an array of numbers as argument and will return a new array with distinct elements
Solution 1
https://codeguppy.com/code.html?OkbtP1ZksGHXwqk7Jh3i
var ar = getDistinctElements([1, 2, 3, 6, -1, 2, 9, 7, 10, -1, 100]);
println(ar);
function getDistinctElements(ar)
{
var ar2 = [];
for(let i = 0; i < ar.length; i++)
{
if (!isInArray(ar[i], ar2))
{
ar2.push(ar[i]);
}
}
return ar2;
}
function isInArray(n, ar)
{
for(let i = 0; i < ar.length; i++)
{
if (ar[i] === n)
return true;
}
return false;
}
Coding challenge #27: Create a function that will receive an array of numbers as argument and will return a new array with distinct elements
Solution 2
https://codeguppy.com/code.html?NjGtyQdMP49QiaAkmwpU
var ar = getDistinctElements([1, 2, 3, 6, -1, 2, 9, 7, 10, -1, 100]);
println(ar);
function getDistinctElements(ar)
{
var ar2 = [];
var lastIndex = ar.length - 1;
for(let i = 0; i <= lastIndex; i++)
{
if (!isInArray(ar[i], ar, i + 1, lastIndex))
{
ar2.push(ar[i]);
}
}
return ar2;
}
function isInArray(n, ar, fromIndex, toIndex)
{
for(var i = fromIndex; i <= toIndex; i++)
{
if (ar[i] === n)
return true;
}
return false;
}
Coding challenge #28: Calculate the sum of first 100 prime numbers
https://codeguppy.com/code.html?v0O9sBfnHbCi1StE2TxA
var n = 10;
println("Sum of first ", n, " primes is ", sumPrimes(10));
function sumPrimes(n)
{
var foundPrimes = 0;
var i = 2;
var sum = 0;
while(foundPrimes < n)
{
if (isPrime(i))
{
foundPrimes++;
sum += i;
}
i++;
}
return sum;
}
// Returns true if number n is prime
function isPrime(n)
{
if (n < 2)
return false;
if (n == 2)
return true;
var maxDiv = Math.sqrt(n);
for(var i = 2; i <= maxDiv; i++)
{
if (n % i === 0)
{
return false;
}
}
return true;
}
Coding challenge #29: Print the distance between the first 100 prime numbers
https://codeguppy.com/code.html?xKQEeKYF1LxZhDhwOH7V
printDistances(100);
// Print distances between the first n prime numbers
function printDistances(n)
{
var lastPrime = 2;
var i = lastPrime + 1;
var foundPrimes = 1;
while(foundPrimes < n)
{
if (isPrime(i))
{
println(i - lastPrime, "\t", i, " - ", lastPrime);
foundPrimes++;
lastPrime = i;
}
i++;
}
}
// Returns true if number n is prime
function isPrime(n)
{
if (n < 2)
return false;
if (n == 2)
return true;
var maxDiv = Math.sqrt(n);
for(var i = 2; i <= maxDiv; i++)
{
if (n % i === 0)
{
return false;
}
}
return true;
}
Coding challenge #30-a: Create a function that will add two positive numbers of indefinite size. The numbers are received as strings and the result should be also provided as string.
Solution 1
https://codeguppy.com/code.html?v5A0QBsdHaiAVA2CPN5y
var n1 = "2909034221912398942349";
var n2 = "1290923909029309499";
var sum = add(n1, n2);
println(n1, "\n", n2, "\n", sum);
function add(sNumber1, sNumber2)
{
var s = "";
var carry = 0;
var maxSize = Math.max(sNumber1.length, sNumber2.length);
for(var i = 0; i < maxSize; i++)
{
var digit1 = digitFromRight(sNumber1, i);
var digit2 = digitFromRight(sNumber2, i);
var sum = digit1 + digit2 + carry;
var digitSum = sum % 10;
carry = sum >= 10 ? 1 : 0;
s = digitSum.toString() + s;
}
if (carry > 0)
s = carry + s;
return s;
}
function digitFromRight(s, digitNo)
{
if (digitNo >= s.length)
return 0;
var char = s[ s.length - 1 - digitNo ];
return parseInt(char);
}
Coding challenge #30-b: Create a function that will add two positive numbers of indefinite size. The numbers are received as strings and the result should be also provided as string.
Solution 2
https://codeguppy.com/code.html?yMQXcPgfrYxuaIxqQmZc
var n1 = "2909034221912398942349";
var n2 = "1290923909029309499";
var sum = add(n1, n2);
println(n1);
println(n2);
println(sum);
function add(sNumber1, sNumber2)
{
var maxSize = Math.max(sNumber1.length, sNumber2.length);
var s1 = sNumber1.padStart(maxSize, "0");
var s2 = sNumber2.padStart(maxSize, "0");
var s = "";
var carry = 0;
for(var i = maxSize - 1; i >= 0; i--)
{
var digit1 = parseInt(s1[i]);
var digit2 = parseInt(s2[i]);
var sum = digit1 + digit2 + carry;
var digitSum = sum % 10;
carry = sum >= 10 ? 1 : 0;
s = digitSum.toString() + s;
}
if (carry > 0)
s = carry + s;
return s;
}Coding challenge #31a. Create a function that will return the number of words in a text
https://codeguppy.com/code.html?r4kwkcWiHfzQZkM1qrX4
// Solution 1
function countWords(text)
{
var wasSeparator = true;
var words = 0;
for(var c of text)
{
// if current character is separator then advance and
// set that the previous character was separator
if (isSeparator(c))
{
wasSeparator = true;
continue;
}
// if current character is not separator
// ... but if previous was separator...
if (wasSeparator)
{
words++;
wasSeparator = false;
}
}
return words;
}
function isSeparator(c)
{
var separators = [" ", "\t", "\n", "\r", ",", ";", ".", "!", "?"];
return separators.includes(c);
}
println(countWords(""));
println(countWords(" "));
println(countWords("JavaScript!!! "));
println(countWords(" JavaScript"));
println(countWords(" JavaScript is cool "));
println(countWords("I like to learn JavaScript with codeguppy"));
Coding challenge #31b. Create a function that will return the number of words in a text
https://codeguppy.com/code.html?8pdZSfchSXNxBK1f7r7s
// Solution 2
function countWords(text)
{
var words = 0;
if (text.length > 0 && !isSeparator(text[0]))
words++;
for(var i = 1; i < text.length; i++)
{
var currChr = text[i];
var prevChr = text[i - 1];
if (!isSeparator(currChr) && isSeparator(prevChr))
{
words++;
}
}
return words;
}
function isSeparator(c)
{
var separators = [" ", "\t", "\n", "\r", ",", ";", ".", "!", "?"];
return separators.includes(c);
}
println(countWords(""));
println(countWords(" "));
println(countWords("JavaScript!!! "));
println(countWords(" JavaScript"));
println(countWords(" JavaScript is cool "));
println(countWords("I like to learn JavaScript with codeguppy"));Coding challenge #32. Create a function that will capitalize the first letter of each word in a text
https://codeguppy.com/code.html?OJoMXT4GKasSfNeX4hjH
println(captializeWords("Create a function that will capitalize the first letter of each word in a text"));
function captializeWords(text)
{
var text2 = "";
for(var i = 0; i < text.length; i++)
{
var currChr = text[i];
var prevChr = i > 0 ? text[i - 1] : " ";
if (!isSeparator(currChr) && isSeparator(prevChr))
{
currChr = currChr.toUpperCase();
}
text2 += currChr;
}
return text2;
}
function isSeparator(c)
{
var separators = [" ", "\t", "\n", "\r", ",", ";", ".", "!", "?"];
return separators.includes(c);
}
Coding challenge #33. Calculate the sum of numbers received in a comma delimited string
https://codeguppy.com/code.html?QL6H38rpqjGarwCfsbO3
println(sumCSV("1.5, 2.3, 3.1, 4, 5.5, 6, 7, 8, 9, 10.9"));
function sumCSV(s)
{
var ar = s.split(",");
var sum = 0;
for(var n of ar)
{
sum += parseFloat(n);
}
return sum;
}
Coding challenge #34. Create a function that will return an array with words inside a text
https://codeguppy.com/code.html?IJI0E4OGnkyTZnoszAzf
var text = "Create a function, that will return an array (of string), with the words inside the text";
println(getWords(text));
function getWords(text)
{
let startWord = -1;
let ar = [];
for(let i = 0; i <= text.length; i++)
{
let c = i < text.length ? text[i] : " ";
if (!isSeparator(c) && startWord < 0)
{
startWord = i;
}
if (isSeparator(c) && startWord >= 0)
{
let word = text.substring(startWord, i);
ar.push(word);
startWord = -1;
}
}
return ar;
}
function isSeparator(c)
{
var separators = [" ", "\t", "\n", "\r", ",", ";", ".", "!", "?", "(", ")"];
return separators.includes(c);
}
Coding challenge #35. Create a function to convert a CSV text to a “bi-dimensional” array
https://codeguppy.com/code.html?5Hqv93WXQ6OOjAYApLGw
var data = "John;Smith;954-000-0000\nMich;Tiger;305-000-0000\nMonique;Vasquez;103-000-0000";
var ar = csvToArray(data);
println(JSON.stringify(ar));
function csvToArray(data)
{
var arLines = data.split("\n");
for(var i = 0; i < arLines.length; i++)
{
var arLine = arLines[i].split(";");
arLines[i] = arLine;
}
return arLines;
}
Coding challenge #36. Create a function that converts a string to an array of characters
https://codeguppy.com/code.html?XCD9vmSQ34HrascysDBL
Coding challenge #36. Create a function that converts a string to an array of characters
https://codeguppy.com/code.html?XCD9vmSQ34HrascysDBL
Coding challenge #37. Create a function that will convert a string in an array containing the ASCII codes of each character
https://codeguppy.com/code.html?suDlTrNYYmCpNJhZpPdB
println(getCharCodes("I like JavaScript"));
function getCharCodes(s)
{
var ar = [];
for(var i = 0; i < s.length; i++)
{
var code = s.charCodeAt(i);
ar.push(code);
}
return ar;
}
Coding challenge #38. Create a function that will convert an array containing ASCII codes in a string
https://codeguppy.com/code.html?QGWEPdBEVk4RFGn6UVhP
println(codesToString([73,32,108,105,107,101,32,74,97,118,97,83,99,114,105,112,116]));
function codesToString(ar)
{
return String.fromCharCode(...ar);
}
Coding challenge #39. Implement the Caesar cypher
https://codeguppy.com/code.html?kextwiVVb9VwhKajJriG
var text = "I LOVE JAVASCRIPT";
var textEnc = encrypt(text, 13);
var textDec = decrypt(textEnc, 13);
println(text);
println(textEnc);
println(textDec);
// Decrypt a message by using the same encrypt function
// ... but using the inverse of the key (e.g. rotate in the other direction)
function decrypt(msg, key)
{
return encrypt(msg, key * -1);
}
// Function will implement Caesar Cipher to
// encrypt / decrypt the msg by shifting the letters
// of the message acording to the key
function encrypt(msg, key)
{
var encMsg = "";
for(var i = 0; i < msg.length; i++)
{
var code = msg.charCodeAt(i);
// Encrypt only letters in 'A' ... 'Z' interval
if (code >= 65 && code <= 65 + 26 - 1)
{
code -= 65;
code = mod(code + key, 26);
code += 65;
}
encMsg += String.fromCharCode(code);
}
return encMsg;
}
// Modulo function: n mod p
function mod(n, p)
{
if ( n < 0 )
n = p - Math.abs(n) % p;
return n % p;
}
Coding challenge #40. Implement the bubble sort algorithm for an array of numbers
https://codeguppy.com/code.html?6bPnKHLhArSPdUPK2mqm
var ar = [23, 1000, 1, -1, 8, 3];
println(ar);
bubbleSort(ar);
println(ar);
function bubbleSort(ar)
{
var shouldSort = true;
var length = ar.length;
while(shouldSort)
{
shouldSort = false;
length--;
for(var i = 0; i < length; i++)
{
var a = ar[i];
if ( a > ar[i+1] )
{
ar[i] = ar[i+1];
ar[i+1] = a;
shouldSort = true;
}
}
}
}
Coding challenge #41. Create a function to calculate the distance between two points defined by their x, y coordinates
https://codeguppy.com/code.html?mnAuF3BjhDaFwBtDUnI4
println(getDistance(100, 100, 400, 300));
function getDistance(x1, y1, x2, y2)
{
var l1 = x2 - x1;
var l2 = y2 - y1;
return Math.sqrt(l1 * l1 + l2 * l2);
}
Coding challenge #42. Create a function that will return a Boolean value indicating if two circles defined by center coordinates and radius are intersecting
https://codeguppy.com/code.html?cTZiewHGAErNUjYRCE6f
println(collisionCircleCircle(200, 200, 100, 300, 300, 50));
function collisionCircleCircle(circle1X, circle1Y, circle1R, circle2X, circle2Y, circle2R)
{
return getDistance(circle1X, circle1Y, circle2X, circle2Y) <= circle1R + circle2R;
}
// Calculate the distance between the two specified points
function getDistance(x1, y1, x2, y2)
{
var l1 = x2 - x1;
var l2 = y2 - y1;
return Math.sqrt(l1 * l1 + l2 * l2);
}
Coding challenge 43. Create a function that will receive a bi-dimensional array as argument and a number and will extract as a unidimensional array the column specified by the number
https://codeguppy.com/code.html?b22i9I5CUkFTdHF4Bod8
var ar = [ ["John", 120],
["Jane", 115],
["Thomas", 123],
["Mel", 112],
["Charley", 122]
];
var numbers = extractCol(ar, 1);
println(numbers);
function extractCol(ar, colNo)
{
var arCol = [];
for(var i = 0; i < ar.length; i++)
{
arCol.push(ar[i][colNo]);
}
return arCol;
}
Coding challenge #44. Create a function that will convert a string containing a binary number into a number
https://codeguppy.com/code.html?iDykr8pqeuTPgZjVAvWv
println(binaryToNumber("11111111"));
function binaryToNumber(sBinary)
{
return parseInt(sBinary, 2);
}
Coding challenge #45. Create a function to calculate the sum of all the numbers in a jagged array (array contains numbers or other arrays of numbers on an unlimited number of levels)
https://codeguppy.com/code.html?3gu4jcQRpBQWu2EsJrv0
var ar = [1, 2, [15, [23], [5, 12]], [100]];
println(sumArray(ar));
function sumArray(ar)
{
var sum = 0;
for(var el of ar)
{
if (Array.isArray(el))
{
el = sumArray(el);
}
sum += el;
}
return sum;
}
Coding challenge #46-a. Find the maximum number in a jagged array of numbers or array of numbers
https://codeguppy.com/code.html?oT5nrxux2yAgIRsuXBSK
// Solution 1
var ar = [2, 4, 10, [12, 4, [100, 99], 4], [3, 2, 99], 0];
var max = findMax(ar);
println("Max = ", max);
// Use recursion to find the maximum numeric value in an array of arrays
function findMax(ar)
{
var max = -Infinity;
// Cycle through all the elements of the array
for(var i = 0; i < ar.length; i++)
{
var el = ar[i];
// If an element is of type array then invoke the same function
// to find out the maximum element of that subarray
if ( Array.isArray(el) )
{
el = findMax( el );
}
if ( el > max )
{
max = el;
}
}
return max;
}
Coding challenge #46-b. Find the maximum number in a jagged array of numbers or array of numbers
https://codeguppy.com/code.html?VvLiW0W3lwnMrbwC9epp
// Solution 2
var ar = [2, 4, 10, [12, 4, [100, 99], 4], [3, 2, 99], 0];
var max = findMax(ar);
println("Max = ", max);
// Use a stack to find the maximum numeric value in an array of arrays
function findMax(arElements)
{
var max = -Infinity;
// This is the stack on which will put the first array and then
// all the other sub-arrays that we find as we traverse an array
var arrays = [];
arrays.push(arElements);
// Loop as long as are arrays added to the stack for processing
while(arrays.length > 0)
{
// Extract an array from the stack
ar = arrays.pop();
// ... and loop through its elements
for(var i = 0; i < ar.length; i++)
{
var el = ar[i];
// If an element is of type array, we'll add it to stack
// to be processed later
if ( Array.isArray(el) )
{
arrays.push(el);
continue;
}
if ( el > max )
{
max = el;
}
}
}
return max;
}
Coding challenge #47. Deep copy a jagged array with numbers or other arrays in a new array
https://codeguppy.com/code.html?4eRqha7h7kjOLnDTyf00
var ar1 = [2, 4, 10, [12, 4, [100, 99], 4], [3, 2, 99], 0];
var ar2 = copyArray(ar1);
println(ar2);
function copyArray(ar)
{
var ar2 = [];
for(var el of ar)
{
if (Array.isArray(el))
{
el = copyArray(el);
}
ar2.push(el);
}
return ar2;
}
Coding challenge #48. Create a function to return the longest word(s) in a string
https://codeguppy.com/code.html?6O219iv12e5UaC30fcbG
var text = "Create a function to return the longest word(s) in a sentance.";
println(getLongestWords(text));
function getLongestWords(text)
{
var words = getWords(text);
var maxSize = 0;
var maxPositions = [];
for(var i = 0; i < words.length; i++)
{
var currWordSize = words[i].length;
if (currWordSize > maxSize)
{
maxSize = currWordSize;
maxPositions = [ i ];
}
else if (currWordSize === maxSize)
{
maxPositions.push(i);
}
}
return getElements(words, maxPositions);
}
// Get only the elements from specified positions from the array
function getElements(ar, arPositions)
{
var arNew = [];
for(var pos of arPositions)
{
arNew.push(ar[pos]);
}
return arNew;
}
// Returns an array with the words from specified text
function getWords(text)
{
let startWord = -1;
let ar = [];
for(let i = 0; i <= text.length; i++)
{
let c = i < text.length ? text[i] : " ";
if (!isSeparator(c) && startWord < 0)
{
startWord = i;
}
if (isSeparator(c) && startWord >= 0)
{
let word = text.substring(startWord, i);
ar.push(word);
startWord = -1;
}
}
return ar;
}
function isSeparator(c)
{
var separators = [" ", "\t", "\n", "\r", ",", ";", ".", "!", "?", "(", ")"];
return separators.includes(c);
}
Coding challenge #49. Shuffle an array of strings
https://codeguppy.com/code.html?EHvbHKy5uPvSKxsaeqWv
var ar = ["Shuffle", "an", "array", "of", "strings"];
println(shuffleArray(ar));
// Shuffle array implemented using Fisher–Yates shuffle algorithm
function shuffleArray(ar)
{
for(var i = ar.length - 1; i > 0; i--)
{
var j = randomInt(0, i - 1);
var t = ar[i];
ar[i] = ar[j];
ar[j] = t;
}
return ar;
}
// Get a random int between min and max (both included)
function randomInt(min, max)
{
return Math.floor(Math.random() * (max - min + 1) ) + min;
}
Coding challenge #50. Create a function that will receive n as argument and return an array of n unique random numbers from 1 to n.
https://codeguppy.com/code.html?GfCrzPkGSPKbvLuf6KyA
println(getRandomNumbers(10));
function getRandomNumbers(n)
{
var ar = [];
for(var i = 1; i <= n; i++)
{
ar.push(i);
}
shuffleArray(ar);
return ar;
}
// Shuffle array implemented using Fisher–Yates shuffle algorithm
function shuffleArray(ar)
{
for(var i = ar.length - 1; i > 0; i--)
{
var j = randomInt(0, i - 1);
var t = ar[i];
ar[i] = ar[j];
ar[j] = t;
}
return ar;
}
// Get a random int between min and max (both included)
function randomInt(min, max)
{
return Math.floor(Math.random() * (max - min + 1) ) + min;
}
Coding challenge #51. Find the frequency of characters inside a string. Return the result as an array of objects. Each object has 2 fields: character and number of occurrences.
https://codeguppy.com/code.html?e8wHQuJmeYCDKml5k07d
var ar = getCharFrequency("Find the frequency of characters inside a string");
println(JSON.stringify(ar));
function getCharFrequency(text)
{
var ar = [];
for(var chr of text)
{
updateFrequency(ar, chr);
}
return ar;
}
function updateFrequency(ar, chr)
{
for(var el of ar)
{
if (el.chr === chr)
{
el.count++;
}
}
ar.push({ chr : chr, count : 1 });
}
Coding challenge #52. Calculate Fibonacci(500) with high precision (all decimals)
https://codeguppy.com/code.html?OD5GDYyCVo4wgTRCXzRU
println(fibonacci(500));
function fibonacci(n)
{
if (n === 0)
return "0";
if (n === 1)
return "1";
var n1 = "0";
var n2 = "1";
for(var i = 2; i <= n; i++)
{
var sum = add(n1, n2);
n1 = n2;
n2 = sum;
}
return n2;
}
function add(sNumber1, sNumber2)
{
var maxSize = Math.max(sNumber1.length, sNumber2.length);
var s1 = sNumber1.padStart(maxSize, "0");
var s2 = sNumber2.padStart(maxSize, "0");
var s = "";
var carry = 0;
for(var i = maxSize - 1; i >= 0; i--)
{
var digit1 = parseInt(s1[i]);
var digit2 = parseInt(s2[i]);
var sum = digit1 + digit2 + carry;
var digitSum = sum % 10;
carry = sum >= 10 ? 1 : 0;
s = digitSum.toString() + s;
}
if (carry > 0)
s = carry + s;
return s;
}
Coding challenge #53. Calculate 70! with high precision (all digits)
https://codeguppy.com/code.html?m4AfgJmCABGNEvKlUNtM
println(factorial(70));
// Calculate factorial(n) ... using big number calculations
function factorial(n)
{
var prod = "1";
for(var i = 2; i <= n; i++)
{
prod = mult(prod, i.toString());
}
return prod;
}
// Multiplies sNumber1 * sNumber2
// Each number is provided as string
function mult(sNumber1, sNumber2)
{
// Calculate partial results according to multiplication algorithm
var partialResults = [];
for(var i = sNumber2.length - 1; i >= 0; i--)
{
var digit = parseInt(sNumber2[i]);
var partialResult = multDigit(sNumber1, digit);
partialResult += "0".repeat(partialResults.length);
partialResults.push(partialResult);
}
// Sum partial results to obtain the product
var sum = "";
for(var r of partialResults)
{
sum = add(sum, r);
}
return sum;
}
// Multiplies number sNumber (as string) with a single digit number
function multDigit(sNumber, digit)
{
var p = "";
var carry = 0;
for(var i = sNumber.length - 1; i >= 0; i--)
{
var numberDigit = parseInt(sNumber[i]);
var prod = digit * numberDigit + carry;
var prodDigit = prod % 10;
carry = Math.floor(prod / 10);
p = prodDigit.toString() + p;
}
if (carry > 0)
p = carry + p;
return p;
}
function add(sNumber1, sNumber2)
{
var maxSize = Math.max(sNumber1.length, sNumber2.length);
var s1 = sNumber1.padStart(maxSize, "0");
var s2 = sNumber2.padStart(maxSize, "0");
var s = "";
var carry = 0;
for(var i = maxSize - 1; i >= 0; i--)
{
var digit1 = parseInt(s1[i]);
var digit2 = parseInt(s2[i]);
var sum = digit1 + digit2 + carry;
var digitSum = sum % 10;
carry = sum >= 10 ? 1 : 0;
s = digitSum.toString() + s;
}
if (carry > 0)
s = carry + s;
return s;
}If you have a github account you can fork the entire repository with these challenges from https://github.com/CodeGuppyPrograms/CodingChallenges
I hope you had fun browsing through these coding challenges. If you like them, and you want more coding challenges for beginners please leave a comment or send a tweet to @codeguppy.
Happy coding!
Previously published at https://github.com/CodeGuppyPrograms/CodingChallenges
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