HDU 2516 取石子游戏（斐波那契博弈）

取石子游戏

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 6613    Accepted Submission(s): 3994

Problem Description

1堆石子有n个,两人轮流取.先取者第1次可以取任意多个，但不能全部取完.以后每次取的石子数不能超过上次取子数的2倍。取完者胜.先取者负输出"Second win".先取者胜输出"First win".

 

Input

输入有多组.每组第1行是2<=n<2^31. n=0退出.

 

 

Output

先取者负输出"Second win". 先取者胜输出"First win". 
参看Sample Output.

 

 

Sample Input

2 13 10000 0

 

Sample Output

Second win Second win First win

code

#include<cstdio>
#include<algorithm>
#include<iostream>

using namespace std;

int f[50];

int main () {
    f[1] = 1;f[2] = 2;
    for (int i=3; i<=45; ++i) {
        f[i] = f[i-1] + f[i-2];
    }
    int n;
    while (cin >> n && n) {
        bool flag = false;
        for (int i=1; i<=45; ++i)
            if (f[i] == n) {flag = true;break;}
        if (flag) puts("Second win");
        else puts("First win");
    }
}