zoj 2374 Marbles on a tree

#include<iostream>#include<vector>#include<cstdio>#include<set>#include<map>#include<algorithm>#include<string.h>#include<queue>using namespace std;enum {    SIZ = 10008,};struct Node {    int p;    int n;     int cnt; };Node tree[SIZ];int val = 0, num;void readIn(queue<int> &q){    tree[0].p = 0; tree[0].n = num; tree[0].cnt = 0;    tree[1].p = 0;    int i, n, cnt, d, t;    for(i=1;i<=num;i++){        scanf("%d%d%d",&n,&cnt,&d);        tree[n].cnt = cnt;        tree[n].n = d;        if(d==0) q.push(n);        while(d--){ scanf("%d",&t); tree[t].p = n;        }    }}int fun(){    queue<int> q;    readIn(q);    int cur, p;    val = 0;    while(!q.empty()){        cur = q.front(); q.pop();        p = tree[cur].p;        tree[cur].cnt --;        if(tree[cur].cnt != 0){ tree[p].cnt += tree[cur].cnt; if(tree[cur].cnt > 0){     val += tree[cur].cnt; } else {     val -= tree[cur].cnt; }        }        if(--tree[p].n==0){ q.push(p);        }    }    return val;}int main(){    scanf("%d",&num);    while(num){        cout<<fun()<<endl;        scanf("%d",&num);    }    return 0;}