P1129 [ZJOI2007] 矩阵游戏

https://www.luogu.com.cn/record/98680044

Luogu/P1129/P1129.cpp

@@ -0,0 +1,58 @@
+#include <iostream>
+#include <functional>
+#include <vector>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    int t;
+
+    cin >> t;
+
+    while (t--) {
+        int n;
+
+        cin >> n;
+
+        int ans = 0;
+        std::vector<int> tag(n, -1), match(n, -1);
+        std::vector<std::vector<int>> g(n);
+
+        for (int i = 0; i < n; i++) {
+            for (int j = 0, x; j < n; j++) {
+                cin >> x;
+
+                if (x) g[i].emplace_back(j);
+            }
+        }
+
+        std::function<bool(int, int)> dfs = [&](int u, int t) {
+            if (tag[u] == t) return false;
+
+            tag[u] = t;
+
+            for (int v : g[u]) {
+                if (match[v] == -1 || dfs(match[v], t)) {
+                    match[v] = u;
+
+                    return true;
+                }
+            }
+
+            return false;
+        };
+
+        for (int i = 0; i < n; i++) {
+            if (dfs(i, i)) ans++;
+        }
+
+        cout << (ans == n ? "Yes" : "No") << endl;
+    }
+
+    return 0;
+}