This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
const int MAXN = 3E5 + 5;
const int MOD = 1E9 + 7;
int par[MAXN];
struct DSU {
    int n;
    DSU(int n) : n(n) {
        // 23 orz
        iota(par, par + n, 0);
    }
    int get(int x) {
        if(par[x] == x) {
            return x;
        }
        return par[x] = get(par[x]);
    }
    bool same(int a, int b) {
        return get(a) == get(b);
    }
    bool unite(int u, int v) {
        if(same(u, v)) {
            return false;
        }
        u = get(u); 
        v = get(v);
        par[u] = v;
        return true;
    }
};
#define ONLINE_JUDGE
void solve() {
    int n, m;
    cin >> n >> m;
    vector <int> adj[n +1];
    for(int i = 1; i <= n -1; i++) {
        int u, v;
        cin >> u >> v;
        adj[u].emplace_back(v);
        adj[v].emplace_back(u);
    }
    DSU dsu(n +1);
    for(int i = 1; i <= m; i++) {
        int l, r;
        cin >> l >> r;
        if(l > r) {
            swap(l, r);
        }
        for(int i = dsu.get(l); i +1 <= r; i = dsu.get(i +1)) {
            //cerr << i << " " << i +1 << " :: " << dsu.get(i) << " " << dsu.get(i +1) << "\n";
            dsu.unite(i, i +1);
        }
    }
    int ans = 1;
    for(int i = 1; i <= n; i++) {
        if(dsu.get(i) == i) {
            ans = (ans * 2) % MOD;
        }
    }
    cout << ans;
    
    return;
}
signed main() {
    #ifndef ONLINE_JUDGE
        freopen("in.txt", "r", stdin);
        freopen("out.txt", "w", stdout);
    #endif
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);
    int t = 1; //cin >> t;
    for(int i = 1; i <= t; i++) {
        solve();
    }
    return 0;
}
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