// Two Sum II - Input array is sorted
class Solution {
public:
  vector<int> twoSum(vector<int> &a, int target) {
    int i = 0, j = a.size()-1;
    while (i < j) {
      if (a[i]+a[j] < target)
        i++;
      else if (a[i]+a[j] > target)
        j--;
      else
        break;
    }
    return {i+1, j+1};
  }
};