#include using namespace std; const int N = 110, M = N * N; int n; int din[N]; // 链式前向星 int e[M], h[N], idx, w[M], ne[M]; void add(int a, int b, int c = 0) { e[idx] = b, ne[idx] = h[a], w[idx] = c, h[a] = idx++; } vector path; // 求拓扑序的模板 /* ① 所有入度为0的点入队列 ② 队头元素出队,遍历它相临的点,并且将相临的点入度-1 ③ 如果减1后的入度为0,则此点入队列,意味着它的前序依赖已完成 */ void topsort() { queue q; // 所有入度为0的入队列 for (int i = 1; i <= n; i++) if (din[i] == 0) q.push(i); while (q.size()) { int u = q.front(); q.pop(); path.push_back(u); for (int i = h[u]; ~i; i = ne[i]) { int v = e[i]; din[v]--; if (din[v] == 0) q.push(v); } } } int main() { memset(h, -1, sizeof h); scanf("%d", &n); for (int a = 1; a <= n; a++) { int b; while (scanf("%d", &b), b) { // b==0时结束读入 add(a, b); din[b]++; // 入度++ } } // 拓扑序 topsort(); // 输出任意一组拓扑序 for (int i = 0; i < n; i++) printf("%d ", path[i]); return 0; }