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You can use your own function to get all combinations.ExampleFollowing is the code −function combination(values) { function * combinationRepeat(size, v) { if (size) for (var chr of values) yield * combinationRepeat(size - 1, v + chr); else yield v; } return [...combinationRepeat(values.length, "")]; } var output = combination([4,5]); console.log(output);To run the above program, you need to use the following command −node fileName.js.Here, my file name is demo306.js.OutputThis will produce the following output −PS C:\Users\Amit\javascript-code> node demo306.js [ '44', '45', '54', '55' ]
We are required to write a function that compares two arrays and creates a third array filling that array with all the elements of the second array and filling null for all those elements that are present in the first array but misses out in the second array.For example:If the two arrays are −const arr1 = ['f', 'g', 'h']; const arr2 = ['f', 'h'];Then the output should be −const output = ['f', null, 'h'];Therefore, let’s write the code for this function −ExampleThe code for this will be −const arr1 = ['f', 'g', 'h']; const arr2 = ['f', 'h']; const compareAndFill ... Read More
Given an array of integers, we are required to write a function that takes this array and finds the one element that appears an odd number of times.There will always be only one integer that appears an odd number of times. We will approach this problem by sorting the array. Once sorted, we can iterate over the array to pick the element that appears for odd number of times.ExampleThe code for this will be −const arr = [20, 1, -1, 2, -2, 3, 3, 5, 5, 1, 2, 4, 20, 4, -1, -2, 5]; const findOdd = arr => { ... Read More
We are required to write a JavaScript function that takes in an array that contains some numbers, some strings and some false values. Our function should return the biggest Number from the array.For example: If the input array is −const arr = [23, 'hello', undefined, null, 21, 65, NaN, 1, undefined, 'hii'];Then the output should be 65.Therefore, let’s write the code for this function −ExampleThe code for this will be −const arr = [23, 'hello', undefined, null, 21, 65, NaN, 1, undefined, 'hii']; const pickBiggest = arr => { let max = -Infinity; for(let i = 0; i ... Read More
We are required to write a JavaScript function that takes in an array of Numbers. The function should return the middlemost element of the array.For example: If the array is −const arr = [1, 2, 3, 4, 5, 6, 7];Then the output should be 4.ExampleThe code for this will be −const arr = [1, 2, 3, 4, 5, 6, 7]; const middle = function(){ const half = this.length >> 1; const offset = 1 - this.length % 2; return this.slice(half - offset, half + 1); }; Array.prototype.middle = middle; console.log(arr.middle()); console.log([1, 2, 3, 4, 5, 6].middle());OutputThe output in the console will be −[ 4 ] [ 3, 4 ]
We are required to write a JavaScript function that takes in an array of literals and returns a new array that have elements of the original array chunked into subarrays of length exactly 2. Now if the length of original array is not exactly divisible by 2, then the last subarray should have only one element.For example: If the input array is −const arr = [1, 2, 3, 4, 5, 6, 7];Then the output should be −const output = [[1, 2], [3, 4], [5, 6], [7]]Therefore, let’s write the code for this function −ExampleThe code for this will be −const ... Read More
The requirements for this question are simple. We are required to write a JavaScript function that takes in an array of Numbers.If the array contains leading zero, the function should remove the leading zeros in place, otherwise the function should do nothing.For example: If the input array is −const arr = [0, 0, 0, 14, 0, 63, 0];Then the output should be −const output = [14, 0, 63, 0];Therefore, let’s write the code for this function −ExampleThe code for this will be −const arr = [0, 0, 0, 14, 0, 63, 0]; const removeLeadingZero = arr => { while (arr.indexOf(0) === 0) { arr.shift(); }; }; removeLeadingZero(arr); console.log(arr);OutputThe output in the console will be −[ 14, 0, 63, 0 ]
Suppose we have an array of objects like this −const arr = [ {flag: true, other: 1}, {flag: true, other: 2}, {flag: false, other: 3}, {flag: true, other: 4}, {flag: true, other: 5}, {flag: true, other: 6}, {flag: false, other: 7} ];We are required to write a JavaScript function that takes in one such array and sorts it based on the following conditions −If arr.flag === false, the matching element gets placed first in the array, but only after the previous matching elements.The elements that do not match, remain in the same order ... Read More
Given a string that consists of only two types of characters: "(" and ")". We are required to write a function that takes in one such string and balances the parentheses by inserting either a "(" or a ")" as many times as necessary. The function should then return the minimum number of insertions made in the string to balance it.For example: If the string is −const str = '()))';Then the output should be 2, because by prepending '((', we can balance the string.ExampleThe code for this will be −const str = '()))'; const balanceParanthesis = str => { ... Read More
We are required to write a JavaScript function that takes in two arguments −An Array, say arr, of literals that may contain some repeating elements.A number, say limit.The function should validate that no element of the array is repeated more than limit number of times. If any element is repeated more than the limit the function should return false, true otherwise.Therefore, let’s write the code for this function −ExampleThe code for this will be −const arr = [4, 6, 7, 4, 2, 5, 7, 7, 4, 4, 3]; const validateElements = (arr, n) => { const counts = arr.reduce((acc, ... Read More