Find Pair Given Difference.cpp

class Solution {
public:
    int findPair(int n, int x, vector<int> &arr) {
        sort(arr.begin(), arr.end());
        for(int i = 0; i < n; i++) {
            int start = i + 1, end = n - 1, mid;
            while (start <= end) {
                mid = start + (end - start) / 2;
                if (arr[mid] - arr[i] > x) {
                    end = mid - 1;
                } else if (arr[mid] - arr[i] < x) {
                    start = mid + 1;
                } else {
                    return 1;
                }
            }
        }
        return -1;
    }
};