topsort裸题复习

#include <iostream>
#include <cstdio>
#include <vector>
#include <cstring>

using namespace std;

const int N = 110;

int d[N];
int q[N]; int hh = 0, tt = -1;
vector<int> h[N];
int n;
void add(int a, int b)
{
    h[a].push_back(b);
}
void topsort()
{
    for(int i = 1; i <= n; i++)
        if(d[i] == 0) q[++tt] = i;

    while(hh <= tt)
    {
        int t = q[hh++];
        for(int i = 0; i < h[t].size(); i++)
        {
            int j = h[t][i];
            d[j]--;
            if(d[j] == 0) q[++tt] = j;
        }
    }
}
int main()
{
    int x;
    cin >> n;
    for(int i = 1; i <= n; i++)
    {
        while(cin >> x, x)
        {
            add(i, x);
            d[x]++;
        }
    }

    topsort();

    for(int i = 0; i < n; i++)
        cout << q[i] << ' ';
    return 0;
}