Given an array A[] and a number x, check for pair in A[] with sum as x
http://www.geeksforgeeks.org/write-a-c-program-that-given-a-set-a-of-n-numbers-and-another-number-x-determines-whether-or-not-there-exist-two-elements-in-s-whose-sum-is-exactly-x/
public int[] twoSum(int[] numbers, int target) { // Start typing your Java solution below // DO NOT write main() function int[] r = {}; if(numbers == null|| numbers.length == 0) return r; int n = numbers.length; r = new int[n]; int count=0; int i =0,temp= 0; //set a large array. int[] binMap = new int[10000]; for(i =0;i<n;i++) { temp = target-numbers[i]; if(temp>=0 && (binMap[temp]==1)) { r[count++]=numbers[i]; r[count++]= temp; } binMap[numbers[i]] =1; } return r; } }