BZOJ 1603 Usaco 打谷机

#include <cstdio>
#include <algorithm>

struct node{
    int u,v,val;
}Edge[10005];

int n,Out[10005];

void dfs(int x,int now){
    if(x>=n) return;
    int v = Edge[x].v;
    if(Edge[x].val)    now = (now+1)%2;
    Out[v] = now;
    dfs(v,now);
    return;
}

int main(){
    scanf("%d",&n);
    for(int i=1;i<n;i++){
        int x,y,z;
        scanf("%d%d%d",&x,&y,&z);
        Edge[x].v=y;
        Edge[x].val=z;
    }
    dfs(1,0);
    printf("%d\n",Out[n]);
}