#include <iostream>
#include <vector>
#include <cstring>
using namespace std;
const int maxn = 150 + 10;
const int inf = 0x3f3f3f3f;
int n, m, tot, ans = inf, id[maxn], sz[maxn], f[maxn][maxn];
vector<int> e[maxn];
void dfs(int u, int pa) {
	sz[u] = 1;
	for (int v : e[u]) if (v != pa) dfs(v, u), sz[u] += sz[v];
	id[++tot] = u;
}
int main() {
	ios::sync_with_stdio(false);
	cin >> n >> m;
	for (int i = 1; i < n; i++) {
		int u, v; cin >> u >> v;
		e[u].push_back(v); e[v].push_back(u);
	} memset(f, 0x3f, sizeof(f));
	dfs(1, 0); for (int i = 0; i <= n; i++) f[i][0] = 0;
	for (int i = 1; i <= n; i++) f[i][1] = 0;
	for (int i = 1; i <= n; i++)
		for (int j = 2; j <= n; j++) {
			f[i][j] = f[i - sz[id[i]]][j];
			if (j >= sz[id[i]]) f[i][j] = min(f[i][j], f[i - 1][j - sz[id[i]]] + 1);
		}
	for (int i = 1; i <= n; i++) ans = min(ans, f[i][m]);
	cout << ans << '\n';
	return 0;
}