using namespace std;

#include<iomanip>
#include<cmath>
#include<algorithm>
#include<vector>
#include<set>
#include<string>
#include<map>
#include<queue>
#include<stack>
#include<utility>
#include<cstdio>
#include<cstdlib>
#include<cassert>
#include<numeric>
#include<cstring>
#include<sstream>
#include<algorithm>
#include<deque>

const int INFI=(1LL<<30)-100;
const long long INFL=(1LL<<62)-100;
const double eps=1e-10;
const long double pi=acos(-1.0);
const int MAXN=100010;

vector<int> v[MAXN],arb[MAXN];
int lvl[MAXN],fth[MAXN],sons[MAXN];
int dp[MAXN];

int main(){
    freopen("arbore5.in","r",stdin);
    freopen("arbore5.out","w",stdout);

    int n,m;

    scanf("%d%d",&n,&m);

    for(int i=1;i<n;i++){
        int x,y;
        scanf("%d%d",&x,&y);
        v[x].push_back(y);
        v[y].push_back(x);
    }

    queue<int> q;
    q.push(1);
    fth[1]=-1;

    while(!q.empty()){
        int i=q.front();
        q.pop();

        for(unsigned j=0;j<v[i].size();j++){
            int u=v[i][j];
            if(!fth[u]){
                fth[u]=i;
                sons[i]++;
                arb[i].push_back(u);
                q.push(u);
            }
        }
    }

    for(int i=1;i<=m;i++){
        int ax,ay;
        scanf("%d%d",&ax,&ay);
        dp[ax]++;
        dp[ay]++;
    }

    for(int i=1;i<=n;i++){
        if(!sons[i]){
            q.push(i);
        }
    }

    int sum=0;

    while(!q.empty()){
        int i=q.front();
        q.pop();
        if(i==1){
            break;
        }

        for(unsigned j=0;j<arb[i].size();j++){
            dp[i]+=dp[arb[i][j]];
        }

        sum+=(dp[i]%2==0);

        sons[fth[i]]--;
        if(!sons[fth[i]]){
            q.push(fth[i]);
        }
    }

    printf("%d",sum);

    return 0;
}