#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <bitset>
#include <cstdio>
#include <string>
#include <iomanip>
#include <cstring>
#include <cmath>
#include <vector>
#include <algorithm>
#include <unordered_map>
#include <unordered_set>
#include <map>
#include <set>
#include <queue>
#include <stack>
#define int long long
#define lowbit(x) x&(-x)
#define pi 3.14159265358
#define lc k<<1;
#define rc k<<1|1
#define ppb push_back
#define mod 1000000007
#define fori(i,l,r) for(int i=l;i<=r;i++)
#define forj(j,l,r) for(int j=l;j<=r;j++)
using namespace std;
typedef long long ll;
typedef unsigned long long ULL;
typedef pair <int, int> pll;
const int N = 2e6 + 10;
const int P = 131;
int n, m;
int a[N], b[N];
int sum[N];
vector<vector<int>>g(100010);
int ans;
int d[N];
map<pair<int, int>, int>z, mp;
vector<int>v;
void dfs(int u, int fa, int su) {

	for (auto x : g[u]) {
		if (x == fa) continue;
		if (mp[ {u, x}] == 1) {
			su *= z[ {u, x}];
			ans = (ans + (su % mod * b[x]) % mod) % mod;
			dfs(x, u, su);
		} else {
			mp[ {u, x}] = 1;
			ans = (ans + ((su + a[u]) * (z[ {u, x}]) % mod * b[x]) % mod) % mod;
//			cout<<su<<" -- "<<x<<"****\n";
			dfs(x, u, (su * (z[ {u, x}]) + a[u]) % mod);

		}
	}
}

signed main() {
	ios::sync_with_stdio(0);
	cin.tie();
	cout.tie();
	while (cin >> n >> m) {
		mp.clear();
		v.clear();
		z.clear();
		for (int i = 1; i <= n; i++) {
			cin >> a[i] >> b[i];
			d[i] = 0;
			g[i].clear();
		}
		for (int i = 1; i <= m; i++) {
			int u, v;
			cin >> u >> v;
			if (z[ {u, v}]) {
				z[ {u, v}]++;
				continue;
			}
			d[v]++;
			g[u].push_back(v);
			z[ {u, v}]++;
		}
		for (int i = 1; i <= n; i++) {
			if (d[i] == 0) {
				v.push_back(i);
			}
		}
		ans = 0;
		for (auto x : v) {
//			cout << x << "*\n";
			dfs(x, 0, 0);
//			cout << ans << "***\n";
		}
		cout << ans << "\n";
	}
}