poj 2367 Genealogical tree

裸的拓扑排序。

#include <iostream>
#include<stdio.h>
#include<cstring>
#include<vector>
using namespace std;
vector<int>a[105];
int from[105],to[105],flag[105];//出度，入度，标记是否访问过
int main()
{
int n,temp;
scanf("%d",&n);
memset(from,0,sizeof(from));
memset(to,0,sizeof(to));
memset(flag,0,sizeof(flag));
for(int i=1;i<=n;i++){
while(scanf("%d",&temp),temp){
a[i].push_back(temp);
from[i]++;
to[temp]++;
}
}
int count=0;
while(count!=n){
for(int i=1;i<=n;i++){
if(to[i]==0&&flag[i]==0){
count++;
printf("%d ",i);
flag[i]=1;
int len=a[i].size();
for(int j=0;j<len;j++){
to[a[i][j]]--;
}
}
}
}
printf("\n");
return 0;
}