Problem Description
Recently kiki has nothing to do. While she is bored, an idea appears in his mind, she just playes the checkerboard game.The size of the chesserboard is n*m.First of all, a coin is placed in the top right corner(1,m). Each time one people can move the coin into the left, the underneath or the left-underneath blank space.The person who can’t make a move will lose the game. kiki plays it with ZZ.The game always starts with kiki. If both play perfectly, who will win the game?
Input
Input contains multiple test cases. Each line contains two integer n, m (0<n,m<=2000). The input is terminated when n=0 and m=0.
Output
If kiki wins the game printf “Wonderful!”, else “What a pity!”.
Sample Input
5 3
5 4
6 6
0 0
Sample Output
What a pity!
Wonderful!
Wonderful!
Author
月野兔
Source
HDU 2007-11 Programming Contest
解析:
定义两个状态
P:即必败点，某玩家位于此点，只要对方无失误，则必败
N:即必胜点，某玩家位于此点，只要自己无失误，则必胜
三个定理:
一·所有终结点都是必败点P
二.所有一步能走到必败点P的就是N点
三.通过一步操作只能到N点的就是P点
下面就是P/N图
最左下角一定是终结点所以是P
由上图可知n和m为奇数时，kiki都是必输的
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
using namespace std;
int main() {
int n, m;
while(~scanf("%d %d",&n,&m)&&n&&m)
{
if((n&1)&&(m&1)) cout<<"What a pity!"<<endl;
else cout<<"Wonderful!"<<endl;
}
}