// in the name of Allah #include <bits/stdc++.h> const int maxn = 1e5 + 100; int n, ans; int memo[maxn]; bool mark[maxn]; int fib(int k) { if (mark[k]) return memo[k]; mark[k] = true; return memo[k] = fib(k - 1) + fib(k - 2); } int main() { // cin >> n; n = 10; mark[0] = mark[1] = true; memo[1] = 1; for (int i = 1; i <= n; i++) { ans += fib(i); } cout << ans << endl; }