#include <iostream>
#include <cstdio>
#include <cstring>
#include <queue>
using namespace std;
typedef long long ll;
typedef pair<int, int> p;
const int maxn(1e5 + 10);
const int maxm(2e5 + 10);
int n, m, ecnt, head[maxn];
int d[maxn], dep[maxn], f[maxn][17];
struct edge {
int to, nxt;
} edges[maxm];
template<typename T>
inline const T read()
{
T x = 0, f = 1;
char ch = getchar();
while (ch < '0' || ch > '9') {
if (ch == '-') f = -1;
ch = getchar();
}
while (ch >= '0' && ch <= '9') {
x = (x << 3) + (x << 1) + ch - '0';
ch = getchar();
}
return x * f;
}
template<typename T>
inline void write(T x, bool ln)
{
if (x < 0) {
putchar('-');
x = -x;
}
if (x > 9) write(x / 10, false);
putchar(x % 10 + '0');
if (ln) putchar(10);
}
void addEdge(int u, int v)
{
edges[ecnt].to = v;
edges[ecnt].nxt = head[u];
head[u] = ecnt++;
}
void bfs(int root)
{
dep[root] = 1;
queue<int> q;
q.push(root);
while (not q.empty()) {
int u = q.front();
q.pop();
for (int i = head[u]; compl i; i = edges[i].nxt) {
int v = edges[i].to;
if (not dep[v]) {
q.push(v);
dep[v] = dep[u] + 1;
f[v][0] = u;
for (int j = 1; j < 17; ++j) {
f[v][j] = f[f[v][j - 1]][j - 1];
}
}
}
}
}
int lca(int u, int v)
{
if (dep[u] < dep[v]) {
swap(u, v);
}
for (int i = 16; i >= 0; --i) {
if (dep[f[u][i]] >= dep[v]) {
u = f[u][i];
}
}
if (u == v) {
return u;
}
for (int i = 16; i >= 0; --i) {
if (f[u][i] not_eq f[v][i]) {
u = f[u][i];
v = f[v][i];
}
}
return f[u][0];
}
int dfs(int cur, int pre, int& sum)
{
int res = d[cur];
for (int i = head[cur]; compl i; i = edges[i].nxt) {
int nxt = edges[i].to;
if (nxt not_eq pre) {
int val = dfs(nxt, cur, sum);
res += val;
if (not val) {
sum += m;
} else if (val == 1) {
sum += 1;
}
}
}
return res;
}
int main()
{
#ifdef ONLINE_JUDGE
#else
freopen("input.txt", "r", stdin);
#endif
ios::sync_with_stdio(false);
n = read<int>();
m = read<int>();
memset(head, -1, sizeof head);
for (int i = 0; i < n - 1; ++i) {
int u = read<int>(), v = read<int>();
addEdge(u, v);
addEdge(v, u);
}
bfs(1);
for (int i = 0; i < m; ++i) {
int u = read<int>(), v = read<int>();
d[u] += 1;
d[v] += 1;
d[lca(u, v)] -= 2;
}
int sum = 0;
dfs(1, 0, sum);
write(sum, true);
return 0;
}