The second largest value can be found in, for example, the sequence \(A'\) obtained by sorting \(A\). When \(A\) is sorted in ascending order, the second last value, or \(A'_{N-1}\), is the second largest value.

Next, find the position of that value in \(A\) using for and if statements.

Sample code (C++):

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

int main() {
    int n;
    cin >> n;
    vector<int> a(n);
    for(auto &v : a) cin >> v;
    auto b = a;
    sort(b.begin(), b.end());
    int tar = b[n - 2];
    for(int i = 0; i < n; i++) {
        if(a[i] == tar) {
            cout << i + 1 << endl;
        }
    }
}