POJ 2367 Topology

#include <iostream>
#include <vector>
#include <queue>
const int MAXN = 105;


int ind[MAXN];

std::vector<int> children[MAXN];

void topo(int n)
{
	std::queue<int> q;
	for(int i = 1; i <= n; i++)
	{
		if(ind[i] == 0)
			q.push(i);
	}

	while(!q.empty())
	{
		int cur = q.front();
		printf("%d ", cur);
		q.pop();
		int childrenCnt = children[cur].size();
		for(int i = 0; i < childrenCnt; i++)
		{
			ind[children[cur][i]]--;
			if(ind[children[cur][i]] == 0)
				q.push(children[cur][i]);
		}

	}
}

int main()
{
	int n;
	int tmp;
	scanf("%d", &n);
	for(int i = 1; i <= n; i++)
	{
		while(1)
		{
			scanf("%d", &tmp);
			if(tmp == 0)
				break;
			children[i].push_back(tmp);
			ind[tmp]++;
		}
	}
	topo(n);
	printf("\n");
	return 0;
}