Vinit Khandelwal

16. 3Sum Closest Medium Given an array  nums  of  n  integers and an integer  target , find three integers in  nums  such that the sum is closest to  target . Return the sum of the three integers. You may assume that each input would have exactly one solution. Example: Given array nums = [-1, 2, 1, -4], and target = 1. The sum that is closest to the target is 2. (-1 + 2 + 1 = 2). Here is a Javascript Solution to the 3Sum Closest Problem from Leetcode: const threeSum = (arr, sum) => { const ilength = arr.length-2; const jlength = ilength+1; let total; let closest = Infinity; let diff = Math.abs(closest - sum); for(let i=0, j=i+1, k=j+1; i<ilength; i++, j++, k++) { total = arr[i]+arr[j]+arr[k]; if (diff > (Math.abs(total - sum))) { closest = total; if (closest === sum) { break; } diff = Math.abs(closest - sum); } if (j<jlength) { i--; } else...

Find all groups of three values from an array that add up to the given value const threeSum = ( arr , sum ) => { const ans = []; const ilength = arr . length - 2 ; const jlength = ilength + 1 ; let check = false ; for ( let i = 0 , j = i + 1 , k = j + 1 ; i < ilength ; i ++, j ++, k ++) { if ( arr [ i ]+ arr [ j ]+ arr [ k ] === sum ) { ans . push ([ arr [ i ], arr [ j ], arr [ k ]]); } if ( j < jlength ) { i --; } else { j = i + 1 ; } if ( k < arr . length ) { j --; } else { k = j + 1 ; } } return ans ; } Test Input console . log ( threeSum ([- 1 , 0 , 1 , 2 , - 1 , - 4 , - 3 , 5 , - 6 , 0 ], 4 )) Output [ [ - 1 , 0 , 5 ], [ - 1 , 5 , 0 ], [ 0 , - 1 , 5 ], [ 2 , - 3 , 5 ], [ - 1 , 5 , 0 ] ] Run the code here:  https://repl.it/@VinitKhandelwal/15-leetcode-3sum

Longest Common Prefix Easy Write a function to find the longest common prefix string amongst an array of strings. If there is no common prefix, return an empty string  "" . Example 1: Input: ["flower","flow","flight"] Output: "fl" Example 2: Input: ["dog","racecar","car"] Output: "" Explanation: There is no common prefix among the input strings. Note: All given inputs are in lowercase letters  a-z . Javascript Solution to the Longest Common Prefix Problem const longestPrefix = arr => { if (arr.length === 0) { return ""; } if (arr.length === 1) { return arr[0]; } let end = 0; let check = false for (let j = 0; j < arr[0].length; j++){ for (let i = 1; i < arr.length; i++) { if (arr[0][j] !== arr[i][j]) { check = true; break; } } if (check) { break; } end++; } return (ar...