#include <algorithm>
#include <iostream>
#include <fstream>
#include <cstdio>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <cmath>
#include <functional>
#include <cassert>
#include <iomanip>
#include <array>
#include <time.h>
#include <limits.h>
#include <numeric>
#define debug(x) cout<<#x<<": "<<x<<endl
#define rep(i,n) for (int i=0;i<(n);i++)
#define FOR(i,a,b) for (int i=(a);i<=(b);i++)
using namespace std;

typedef vector<int> vi;

long long mod2(long long n){
	return n % 1000000007;
}

void solve(){
#ifdef _WIN32
	istream &cin = ifstream("input.txt");
#endif
	long long n, ans = 0;
	cin >> n;
	rep(i, n){
		long long t1, t2;
		cin >> t1 >> t2;
		t1 = ceil((double)t1 / 2);
		cout << t1 << endl;
		ans += mod2(mod2(t1) * mod2(t2));
		ans = mod2(ans);
	}

	cout << ans << endl;

}

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);

	solve();
	system("PAUSE");
	return 0;
}