pku 2425 A Chess Game(SG函数)

额，没什么可讲的，要讲我也讲不清楚，大家还是去看SG函数吧。

#include <vector> #include <iostream>using namespace std;vector<int> edges[1000];int N,M,GS[1000],ans;int DFS(int n){if(GS[n]!=-1) return GS[n];bool used[1000];memset(used,0,sizeof(used));for(int i=0;i<edges[n].size();i++){used[DFS(edges[n][i])]=true;}int i=0;while(used[i]) i++;return GS[n]=i;}int main(){int num,next;while(scanf("%d",&N)!=EOF){for(int i=0;i<N;i++){edges[i].clear();scanf("%d",&num);for(int j=0;j<num;j++){scanf("%d",&next);edges[i].push_back(next);}}memset(GS,-1,sizeof(GS));while(scanf("%d",&M)&&M){ans=0;for(int i=0;i<M;i++) scanf("%d",&next),ans^=DFS(next);if(ans) printf("WIN/n");else printf("LOSE/n");}}return 0;}