Submission

Score: 90

User: ChanakanStudy

Problemset: อนุกรม

Language: cpp

Time: 0.004 second

Submitted On: 2026-10-10 11:30:15

#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <utility>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <numeric>
#include <iomanip>
using namespace std;
using ll = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    ll a[91];
    int n;
    cin >> n;

    a[0] = 1;
    a[1] = 1;
    ll sum =0;

    for(int i = 2;i<n;i++) {
        sum = a[i-2] + a[i-1];
        a[i] = sum;
    }
    cout << sum;

    return 0;
}