ternary search

#include "bits/stdc++.h"
using namespace std;

int ternarySearch(int l, int r, int x, int arr[]) {
    while (l <= r) {
        int mid1 = l + (r - l) / 3;
        int mid2 = r - (r - l) / 3;

        if (arr[mid1] == x) {
            return mid1;
        }
        if (arr[mid2] == x) {
            return mid2;
        }

        if (x < arr[mid1]) {
            r = mid1 - 1;
        } else if (x > arr[mid2]) {
            l = mid2 + 1;
        } else {
            l = mid1 + 1;
            r = mid2 - 1;
        }
    }
    return -1;
}

signed main() {
    int n, x;
    cin >> n >> x;
    int *arr = new int[n + 1];
    for (int i = 1; i <= n; i++) {
        cin >> arr[i];
    }
    sort(arr + 1, arr + n + 1);
    cout << ternarySearch(1, n, x, arr) << endl;
    return 0;
}