//土尔逊Torson 编写于2023/10/08 #define _CRT_SECURE_NO_WARNINGS #include <iostream> #include <cstdio> using namespace std; const int MAXN145 = 90; long long dp145[MAXN145]; int main() { dp145[0] = 0; dp145[1] = 1; dp145[2] = 2; for (int i = 3; i < MAXN145; ++i) { dp145[i] = dp145[i - 1] + dp145[i - 2]; } int n; while (scanf("%d", &n) != EOF) { printf("%lld\n", dp145[n]); } return 0; } // 64 位输出请用 printf("%lld")