#include<bits/stdc++.h>
#define FILE "read"
#define MAXN 1000010
using namespace std;
struct node{int y,next;}e[MAXN<<1];
int n,m,len,ans,Link[MAXN],d[MAXN],q[MAXN],cnt[MAXN],level[MAXN];
char buf[1<<15],*fs,*ft;
inline char getc(){return (fs==ft&&(ft=(fs=buf)+fread(buf,1,1<<15,stdin),fs==ft))?0:*fs++;}
inline int read(){
	int x=0,f=1;  char ch=getc();
	while(!isdigit(ch))  {if(ch=='-')  f=-1;  ch=getc();}
	while(isdigit(ch))  {x=x*10+ch-'0';  ch=getc();}
	return x*f;
}
void insert(int x,int y){e[++len].next=Link[x];Link[x]=len;e[len].y=y;d[y]++;}
void topsort(){
	int head=0,tail=0;
	for(int i=1;i<=n;++i) if(d[i]==1) q[++tail]=i;
	while(++head<=tail){
		for(int i=Link[q[head]];i;i=e[i].next){
			if(--d[e[i].y]==1){
				q[++tail]=e[i].y;
				level[q[tail]]=level[q[head]]+1;
			}
		}
	}
}
int main(){
	freopen(FILE".in","r",stdin);
	freopen(FILE".out","w",stdout);
	n=read();  m=read();
	for(int i=1;i<n;++i){
		int x=read(),y=read();
		insert(x,y);  insert(y,x);
	}
	topsort();
	for(int i=1;i<=n;++i)  cnt[level[i]]++;
	for(int i=0;cnt[i];++i)  ans+=min(m*2,cnt[i]);
	printf("%d\n",ans);
	return 0;
}