uva 11137

劉汝佳《訓練指南》上的博弈例題

用到了組合遊戲和的概念

#include <cstdio>#include <cstring>typedef long long ll;using namespace std;int sg[210],len;char s[210];bool ok[210],can[210];void init(){    bool vis[210];    int i,j;    memset(sg,0,sizeof(sg));    sg[0]=0,sg[1]=1,sg[2]=1,sg[3]=1;    for(i=4;i<=200;i++){        memset(vis,0,sizeof(vis));        for(j=3;j<=5 && j<=i;j++)            vis[sg[i-j]]=1;        for(j=1;j+5<=i;j++)            vis[sg[j]^sg[i-j-5]]=1;        for(j=0;;j++) if(vis[j]==0)break;        sg[i]=j;    }}bool solve(){    int i,j;    bool flag=0,first;    for(i=0;i<len;i++){        if(s[i]=='X'){            if(i<len-1 && i>=1 && s[i-1]=='X'){                if(flag==0){                    printf("WINNING\n");                    flag=1;                    first=1;                }                if(first==1){                    printf("%d",i+2);                    first=0;                }                else printf(" %d",i+2);            }            if(i<len-1 && i>=1 && s[i+1]=='X'){                if(flag==0){                    printf("WINNING\n");                    flag=1;                    first=1;                }                if(first==1){                    printf("%d",i);                    first=0;                }                else printf(" %d",i);            }            if(i>=2 && s[i-2]=='X'){                if(flag==0){                    printf("WINNING\n");                    flag=1;                    first=1;                }                if(first==1){                    printf("%d",i);                    first=0;                }                else printf(" %d",i);            }        }    }    if(flag){        puts("");        return 1;    }    return 0;}int getans(bool * ok){    int cou=0,i,ans=0;    for(i=0;i<len;i++){        if(ok[i]) cou++;        else if(ok[i]==0){            ans^=sg[cou];            cou=0;        }    }    ans^=sg[cou];   //這裡不要忘了    return ans;}int main(){    int t,T,i,j,ans;    init();    scanf("%d",&T);    for(t=1;t<=T;t++){        scanf("%s",s);        len=strlen(s);        bool flag=solve();        if(flag==0){            for(i=0;i<len;i++) ok[i]=1;            for(i=0;i<len;i++)                if(s[i]=='X')                    for(j=i-2;j<=i+2;j++)                        if(j>=0 && j<len) ok[j]=0;            ans=getans(ok);            if(ans==0) printf("LOSING\n\n");            else{                printf("WINNING\n");                bool first=1;                for(i=0;i<len;i++){                    if(ok[i]){                        for(j=0;j<len;j++) can[j]=ok[j];                        for(j=i-2;j<=i+2;j++)                            if(j>=0 && j<len) can[j]=0;                        ans=getans(can);                        if(ans==0){                            if(first==1){                                printf("%d",i+1);                                first=0;                            }                            else printf(" %d",i+1);                        }                    }                }                puts("");            }        }    }}