#include <iostream>
#include <cstring>
#include <algorithm>
#include <vector>
using namespace std;

const int N = 100010, M = 200010;
int n, m;
int h[N], e[M], ne[M], tot;
int p[N], mk[N], d[N], ans;
vector<int> query[M];

void add(int a, int b) {
    e[++ tot] = b; ne[tot] = h[a]; h[a] = tot;
}

int find(int x) {
    return x == p[x] ? x: p[x] = find(p[x]);
}

void tarjan(int x) {
    mk[x] = 1;
    for(int i = h[x]; i; i = ne[i]) {
        int y = e[i];
        if(mk[y]) continue;
        tarjan(y);
        p[y] = x;
    }

    mk[x] = 2;
    for(int y : query[x])
        if(mk[y] == 2) {
            d[x] ++; d[y] ++; d[find(y)] -= 2;    
        }
}

int dfs(int x, int fa) {
    int res = d[x];
    for(int i = h[x]; i; i = ne[i]) {
        int y = e[i];
        if(y == fa) continue;

        int s = dfs(y, x);
        if(s == 0) ans += m;
        else if(s == 1) ans ++;
        res += s;
    }
    return res;
}

int main() {
    cin >> n >> m;
    for(int i = 0; i < n - 1; i ++) {
        int a, b;
        scanf("%d%d", &a, &b);
        add(a, b), add(b, a);
    }

    for(int i = 1; i <= n; i ++) p[i] = i;

    for(int i = 0; i < m; i ++) {
        int a, b;
        scanf("%d%d", &a, &b);
        query[a].push_back(b);
        query[b].push_back(a);
    }

    tarjan(1);
    dfs(1, -1);

    printf("%d\n", ans);
    return 0;
}