Submission

Score: 100

User: vern6767

Problemset: อนุกรม

Language: cpp

Time: 0.005 second

Submitted On: 2026-09-21 11:38:21

#include <iostream>
using namespace std;

int main() {
    int n = 0;
    long long a = 1, b = 1, c = 0;
    cin >> n;

    if (n == 1 || n == 2)  {
        cout << 1;
        return 0;
    }
    
    for (int i = 3; i <= n; i++) {
        c = a + b;
        a = b;
        b = c;
    }
    
    cout << c;
    return 0;
}