1282. Game Tree

http://acm.timus.ru/problem.aspx?space=1&num=1282

简单博弈 注意题意的理解

代码：

#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<vector>
#include<queue>
#include<map>
#include<stack>
#include<algorithm>
#include<cmath>

using namespace std;
//#pragma comment(linker,"/STACK:1000000000,1000000000")

#define LL long long

const int INF=0x3f3f3f3f;
const int N=1005;
int win[N];
int L[N];
int head[N];
struct node
{
    int j,next;
}side[N];
int I;
void Add(int i,int j)
{
    side[I].j=j;
    side[I].next=head[i];
    head[i]=I++;
}
int dfs(int x,int w)
{
    if(L[x]!=-2)
    return L[x];
    int k=(w==1)?-1:1;
    for(int t=head[x];t!=-1;t=side[t].next)
    {
        int l=side[t].j;
        if(w==1)
        k=max(k,dfs(l,-w));
        else
        k=min(k,dfs(l,-w));
    }
    return k;
}
int main()
{
    //freopen("data.txt","r",stdin);
    int n;
    while(scanf("%d",&n)!=EOF)
    {
        I=0;
        memset(head,-1,sizeof(head));
        for(int i=1;i<=n;++i)
        {L[i]=-2;win[i]=-2;}
        for(int i=2;i<=n;++i)
        {
            char c;
            int f,k;
            cin>>c>>f;//cout<<c<<" "<<f<<endl;
            Add(f,i);
            if(c=='L')
            {
                cin>>k;
                L[i]=k;
            }
        }
        int tmp=dfs(1,1);
        if(tmp==1)
        cout<<"+1"<<endl;
        else if(tmp==-1)
        cout<<"-1"<<endl;
        else
        cout<<"0"<<endl;
    }
    return 0;
}