Answers for "two sum"

two sum problem in c++

bool twosum(int A[], int N, int X) {
  	sort(A, A+N);
    int i = 0, j = N-1;
    while (i < j) {
        if (A[i] + A[j] == X) return true;
        else if (A[i] + A[j] > X) j--;
        else i++;
    }
    return false;
}

two sum

class Solution {
    public int[] twoSum(int[] nums, int target) {
      int[] arr = new int[2];
        
        HashSet<Integer> hs = new HashSet<>();
        
        for(int i=0; i<nums.length; i++){
            if(hs.contains(target-nums[i])){
                arr[1] = i;
                break;
            }
            hs.add(nums[i]);
        }
        
        for(int i=0; i<nums.length; i++){
            if(nums[i] == target - nums[arr[1]] && arr[1] != i)
                arr[0] = i;
        }
        return arr;
    }
}