C++ 查找序列中元素第一次出现的位置

#include <iostream>
using namespace std;

int main() {
    int n, x;
    cin >> n;
    int arr[n];
    for (int i = 0; i < n; i++) {
        cin >> arr[i];
    }
    cin >> x;
    
    int index = -1;
    for (int i = 0; i < n; i++) {
        if (arr[i] == x) {
            index = i + 1;
            break;
        }
    }
    
    cout << index << endl;
    
    return 0;
}