#include <cstdio>
#include <algorithm>
struct edge {
	int y;
	edge *next;
	edge(int y,edge *next): y(y),next(next) {};
}*a[100005];
int n,K,dep;
int ok[100005];
bool done[100005],get;
void out(int u,int v) {
	ok[u]++;
	if (!v) return;
	for (edge *p = a[u];p;p = p->next) {
		out(p->y,v - 1);
	}
}
void bef(int u,int v) {
	ok[u]--;
	if (!v) return;
	for (edge *p = a[u];p;p = p->next) {
		bef(p->y,v - 1);
	}
}
void dfs(int u) {
	if (u > dep) {
		for (int i = 1;i <= n;i++) if (!ok[i]) {
			return;
		}
		get = 1;
		return;
	}
	for (int i = 1;i <= n;i++) 
		if (!done[i]) {
			done[i] = 0;
			out(i,K);
			dfs(u + 1);
			bef(i,K);
		}
}
int main() {
	freopen("routea.in","r",stdin);
	freopen("routea.out","w",stdout);
	scanf("%d %d",&n,&K);
	if (K == 0) {
		printf("%d",n);
		return 0;
	}
	int p,q;
	for (int i = 1;i < n;i++) {
		scanf("%d %d", &p, &q);
		a[p] = new edge(q,a[p]);
		a[q] = new edge(p,a[q]);
	}
	get = 0;
	for (dep = 1;dep <= n;dep++) {
		dfs(1);
		if (get) {
			printf("%d",dep);
			return 0;
		}
	}
	return 0;
}