'commit'

TangDou/AcWing/TopSort/1191_zdx.cpp

@@ -0,0 +1,48 @@
+#include <bits/stdc++.h>
+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<int> path;
+// 如果要按字典序输出拓扑序，那么使用小顶堆即可
+void topsort() {
+    priority_queue<int, vector<int>, greater<int>> 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.top();
+        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);
+    cin >> n;
+    for (int a = 1; a <= n; a++) {
+        int b;
+        while (cin >> b, b) {
+            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;
+}