Files
python/TangDou/AcWing/LCA/HDU5452_TanXin.cpp

41 lines
1.2 KiB
C++
Raw Normal View History

2025-08-30 18:35:01 +08:00
#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);
}
}