#include<bits/stdc++.h>

using namespace std;
typedef long long ll;
const int mod = 1e9+7;
int main()
{
    int n;
    while(~scanf("%d",&n))
    {
        ll a,b;
        ll ans = 1;
        while(n--)
        {
            scanf("%lld%lld",&a,&b);
            ans = ans * 2 % mod * (a+b)%mod;
        }
        printf("%lld\n",ans);
    }
    return 0;
}