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| #include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <cctype>
using namespace std;
struct ege
{
int to, nex;
} edge[305];
int head[155], sum[155], tot, dp[155][155], n, p;
void addedge(int from, int to)
{
edge[tot].nex = head[from];
edge[tot].to = to;
head[from] = tot++;
}
int countsum(int root, int pre)
{
sum[root] = 1;
for (int i = head[root]; i; i = edge[i].nex)
{
if (edge[i].to != pre)
sum[root] += countsum(edge[i].to, root);
}
return sum[root];
}
void init()
{
for (int i = 0; i <= n; i++)
sum[i] = 0;
for (int i = 0; i <= n; i++)
{
for (int j = 0; j <= n; j++)
dp[i][j] = 1e9;
}
}
void dfs(int root, int pre)
{
dp[root][0] = 0;
dp[root][sum[root]] = 1;
int i, j, k;
for (i = head[root]; i; i = edge[i].nex)
{
if (edge[i].to != pre)
{
dfs(edge[i].to, root);
for (j = sum[root]; j > 0; j--)
{
for (k = 1; k <= sum[edge[i].to] && k <= j; k++)
dp[root][j] = min(dp[root][j], dp[root][j - k] + dp[edge[i].to][k]);
}
}
}
}
int main()
{
while (~scanf("%d%d", &n, &p))
{
init();
tot = 1;
int i, j, u, v, res = 1e9;
for (i = 0; i <= n; i++)
head[i] = 0;
for (i = 1; i < n; i++)
{
scanf("%d%d", &u, &v);
addedge(u, v);
addedge(v, u);
}
for (i = 1; i <= n; i++)
{
init();
countsum(i, -1);
dfs(i, -1);
if (dp[i][n - p] < res)
res = dp[i][n - p];
}
printf("%d\n", res);
}
return 0;
}
|