Is there any way I could Improve my efficiency [on hold]

Question

This is my code for pivot (Problem on Kattis: https://open.kattis.com/problems/pivot ) that passes, but I was wondering what you guys would do to improve efficiency. I initially used a vector (still worked) but thought that an array would be better so I changed it to that.

#include <iostream>
#include <vector>
#include <set>
#include <algorithm>

using namespace std;

int main() {
    set <int> s;
    int n;
    cin >> n;
    int v[n];

    signed int val;
    for (int i = 0; i < n; i++){
        cin >> val;
        v[i] = val;
        s.insert(val);
    }
    int count = 0;
    int i = 0;
    int max = v[0];
    for (int x : s){
        if (v[i] == x && max <= x) {
            count++;
        }
        if (v[i] > max){
            max = v[i];
        }
        i++;
    }
    cout << count << endl;
}

Answer 1

You can use an array to make your code efficient but it limits your boundaries. If you make it dynamic it consumes more spaces in vector. So if you need efficiency so go with an array. But as per your requirement add array and vector both wherever it is needed. try to use less vector