Submission

Score: 90

User: opjns

Problemset: อนุกรม

Language: cpp

Time: 0.002 second

Submitted On: 2025-10-09 09:17:05

#include <iostream>
using namespace std;
int main () {
    int n;
    cin >> n;
    if(n>90||1>n) {
        return 0;
    }
    if(n==1) {
        cout << 1;
    }
    long long first = 0, second = 1, fib =0;
    for (int i = 1; i<n; i++) {
        fib = first + second;
        first = second;
        second = fib;
    }
    cout << fib;
    return 0;
}