Submission

Score: 100

User: koon

Problemset: นักบินอวกาศ

Language: cpp

Time: 0.003 second

Submitted On: 2025-11-04 22:27:08

#include <iostream>
using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    if (n == 0) {
        cout << 0;
        return 0;
    }
    int sum = 4;
    for (int i = 1; i < n; i++) {
        sum += 4+6*i;
    }
    cout << sum;
    return 0;
}