#include <bits/stdc++.h>
using namespace std;
const int MXN = 2e5+5;
int A[MXN];
vector<int> E[MXN];
int dfs(int x,int p,int v){
    v+=A[x];
    if(v>1) return 0;
    int me = !v, ret = 0;
    int emp = 0, down = 0;
    for(int i : E[x]) if(i^p) down++, emp += !A[i];
    
    if(emp && v) me = 1, emp--;
    
    if(emp>1 || (down!=1 && emp>0)) v = 0;
    
    for(int i : E[x]) if(i^p){
        ret += dfs(i,x,v);
    }
    return ret+me;
}
int main() {
    cin.tie(0)->sync_with_stdio(0);
    int n, q; cin >> n >> q;
    for(int i = 1;i<n;i++){
        int a,b; cin >> a >> b;
        E[a].push_back(b);
        E[b].push_back(a);
    }
    for(int i = 0;i<q;i++){
        int a; cin >> a;
        A[a]++;
    }
    cout << dfs(1,0,0);
}