#include <iostream>

#include <cstdio>

#include <cstdlib>

#include <cmath>

#include <algorithm>

#include <cstring>

#include <stack>

#include <cctype>

#include <queue>

#include <string>

#include <vector>

#include<functional>

#include <set>

#include <map>

#include <climits>

#define lson root<<1,l,mid

#define rson root<<1|1,mid+1,r

#define fi first

#define se second

#define ping(x,y) ((x-y)*(x-y))

#define mst(x,y) memset(x,y,sizeof(x))

#define mcp(x,y) memcpy(x,y,sizeof(y))

using namespace std;

#define gamma 0.5772156649015328606065120

#define MOD 1000000007

#define inf 0x3f3f3f3f

#define N 200005

#define maxn 10005

typedef pair<int,int> PII;

typedef long long LL;

int n,m,k,a[N];

LL ans;

vector<int>V[N];

void dfs(int x,int fa){

    for(int u:V[x]){

        if(u==fa)continue;

        dfs(u,x);

        a[x]+=a[u];

        ans+=min(a[u],k-a[u]);

    }

}

int main(){

    int i,j,group,x,y;

    scanf("%d%d",&n,&k);k<<=;

    for(i=;i<=k;++i){

        scanf("%d",&x);

        a[x]=;

    }

    for(i=;i<n;++i){

        scanf("%d%d",&x,&y);

        V[x].push_back(y);

        V[y].push_back(x);

    }

    dfs(,-);

    printf("%I64d\n",ans);

    return ;

}