'commit'

TangDou/AcWing/LCA/HDU5452_TanXin.cpp

@@ -0,0 +1,41 @@
+#include <bits/stdc++.h>
+using namespace std;
+//没仔细研究为什么贪心是对的
+/*
+思路：只能切一条生成树上的边，一个比较直观的想法是只切度数为1的点的那条边，然后枚举这个叶子和外面连接的边数即可
+*/
+const int maxn = 20000 + 7;
+#define inf 1e9
+vector<int> e[maxn];
+int vis[maxn];
+int deg[maxn], degg[maxn];
+int n, m;
+int main() {
+    int T, cas = 1;
+    scanf("%d", &T);
+    while (T--) {
+        memset(deg, 0, sizeof(deg));
+        memset(degg, 0, sizeof(degg));
+        memset(vis, 0, sizeof(vis));
+        printf("Case #%d: ", cas++);
+        scanf("%d%d", &n, &m);
+        for (int i = 0; i < n - 1; i++) {
+            int u, v;
+            scanf("%d%d", &u, &v);
+            deg[u]++;
+            deg[v]++;
+            if (deg[u] > 1) vis[u] = 1;
+            if (deg[v] > 1) vis[v] = 1;
+        }
+        for (int i = 0; i < m - n + 1; i++) {
+            int u, v;
+            scanf("%d%d", &u, &v);
+            degg[u]++;
+            degg[v]++;
+        }
+        int ans = inf;
+        for (int i = 1; i <= n; i++)
+            if (!vis[i]) ans = min(ans, deg[i] + degg[i]);
+        printf("%d\n", ans);
+    }
+}