#include <bits/stdc++.h>
using namespace std;
const int N = 100010, M = 200010;
int depth[N], f[N][25];
int n, m;
int d[N];
int ans;
const int T = 17;

int e[M], h[N], idx, ne[M];
void add(int a, int b) {
    e[idx] = b, ne[idx] = h[a], h[a] = idx++;
}
int start = 1;

void bfs() {
    queue<int> q;
    q.push(start);
    depth[start] = 1;
    while (q.size()) {
        int u = q.front();
        q.pop();
        for (int i = h[u]; ~i; i = ne[i]) {
            int v = e[i];
            if (!depth[v]) {
                depth[v] = depth[u] + 1;
                q.push(v);
                f[v][0] = u;
                for (int k = 1; k <= T; k++) f[v][k] = f[f[v][k - 1]][k - 1];
            }
        }
    }
}

int lca(int a, int b) {
    if (depth[a] < depth[b]) swap(a, b);
    for (int i = T; i >= 0; i--)
        if (depth[f[a][i]] >= depth[b]) a = f[a][i];
    if (a == b) return a;
    for (int i = T; i >= 0; i--)
        if (f[a][i] != f[b][i])
            a = f[a][i], b = f[b][i];
    return f[a][0];
}

void dfs(int u, int fa) {
    for (int i = h[u]; ~i; i = ne[i]) {
        int v = e[i];
        if (v == fa) continue;
        dfs(v, u);
        d[u] += d[v];
    }
}

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

    bfs();

    for (int i = 0; i < m; i++) {
        scanf("%d %d", &a, &b);

        d[a]++, d[b]++;
        int p = lca(a, b);

        d[p] -= 2;
    }

    dfs(start, 0);

    for (int i = 1; i <= n; i++) {
        if (i == start) continue;
        if (d[i] == 0) ans += m;
        if (d[i] == 1) ans += 1;
    }

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