拓扑排序

K.cpp

@@ -0,0 +1,49 @@
+#include <cstring>
+#include <iostream>
+#include <cstdio>
+using namespace std;
+int n, m;
+const int MAXN = 510;
+bool maps[MAXN][MAXN];
+int out[MAXN];
+int in[MAXN];
+int main() {
+ 
+  while (cin >> n >> m) {
+    memset(in, 0, sizeof(in));
+    memset(maps, false, sizeof(maps));
+ 
+    for (int i = 0; i < m; i++) {
+      int x, y;
+      cin >> x >> y;
+      if (maps[x][y] == false) {
+        maps[x][y] = true;
+        in[y]++;
+      }
+    }
+    int cnt = 0;
+    while (cnt < n) {
+      int j = -1;
+      for (int i = 1; i <= n; i++) {
+        if (in[i] == 0) {
+          out[cnt++] = i;
+          in[i] = -1;
+          j = i;
+          break;
+        }
+      }
+      for (int i = 1; i <= n; i++) {
+        if (maps[j][i] == true) {
+          in[i]--;
+          maps[j][i] = false;
+        }
+      }
+    }
+ 
+    cout << out[0];
+    for (int i = 1; i < cnt; i++) {
+      cout << " " << out[i];
+    }
+    cout << endl;
+  }
+}