#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <vector>
#include <iomanip>
#define ALL(x) (x).begin(), (x).end()
#define rt return
#define dll(x) scanf("%I64d",&x)
#define xll(x) printf("%I64d\n",x)
#define sz(a) int(a.size())
#define all(a) a.begin(), a.end()
#define rep(i,x,n) for(int i=x;i<n;i++)
#define repd(i,x,n) for(int i=x;i<=n;i++)
#define pii pair<int,int>
#define pll pair<long long ,long long>
#define gbtb ios::sync_with_stdio(false),cin.tie(0),cout.tie(0)
#define MS0(X) memset((X), 0, sizeof((X)))
#define MSC0(X) memset((X), '\0', sizeof((X)))
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define eps 1e-6
#define gg(x) getInt(&x)
#define db(x) cout<<"== [ "<<x<<" ] =="<<endl;
using namespace std;
typedef long long ll;
ll gcd(ll a,ll b){return b?gcd(b,a%b):a;}
ll lcm(ll a,ll b){return a/gcd(a,b)*b;}
ll powmod(ll a,ll b,ll MOD){ll ans=1;while(b){if(b%2)ans=ans*a%MOD;a=a*a%MOD;b/=2;}return ans;}
inline void getInt(int* p);
const int maxn=100010;
const int inf=0x3f3f3f3f;
/*** TEMPLATE CODE * * STARTS HERE ***/
std::vector<int> son[maxn];
const ll mod=1e9+7ll;
ll ans=0ll;
ll a[maxn];
ll b[maxn];
ll num[maxn];
int du[maxn];
int main()
{// freopen("D:\\common_text\\code_stream\\in.txt","r",stdin);//freopen("D:\\common_text\\code_stream\\out.txt","w",stdout);
    gbtb;int n,m;while(cin>>n>>m){repd(i,1,n){son[i].clear();}MS0(du);MS0(num);repd(i,1,n){cin>>a[i]>>b[i];}int x,y;repd(i,1,m){cin>>x>>y;son[x].push_back(y);du[y]++;}queue<int> q;repd(i,1,n){if(!du[i]){q.push(i);}}ans=0ll;while(q.size()){int temp=q.front();q.pop();for(auto x:son[temp]){ans=(ans+(a[temp]*b[x])%mod+mod)%mod;a[x]+=a[temp];a[x]=(a[x]+mod)%mod;du[x]--;if(!du[x]){q.push(x);}}}cout<<ans<<endl;}return 0;
}inline void getInt(int* p) {char ch;do {ch = getchar();} while (ch == ' ' || ch == '\n');if (ch == '-') {*p = -(getchar() - '0');while ((ch = getchar()) >= '0' && ch <= '9') {*p = *p * 10 - ch + '0';}}else {*p = ch - '0';while ((ch = getchar()) >= '0' && ch <= '9') {*p = *p * 10 + ch - '0';}}
}