import sys
import numpy as np

def cmp(a, b):
    a1, b1 = a
    a2, b2 = b
    return a1 + a2 * b1 >= a2 + a1 * b2


def argsort(A):
    n = A.shape[0]
    length = 20
    INF = np.zeros(2, np.int64)
    INF[1] = 1 << 60
    index = np.arange(n)
    work = np.empty(n, np.int64)
    for l in range(0, n, length):
        r = min(l + length, n)
        for i in range(l+1, r):
            if cmp(A[index[i-1]], A[index[i]]): continue
            tmp = index[i]
            a = A[tmp]
            j = i
            while j > l and not cmp(A[index[j-1]], a):
                index[j] = index[j-1]
                j -= 1
            index[j] = tmp
    while length < n:
        work = index.copy()
        for l in range(0, n, 2 * length):
            li, ri = l, min(l + length, n)
            l_max, r_max = min(li + length, n), min(ri + length, n)
            tot = (l_max - li) + (r_max - ri)
            for i in range(l, l+tot):
                a = A[work[li]] if li < l_max else INF
                b = A[work[ri]] if ri < r_max else INF
                if cmp(a, b):
                    index[i] = work[li]
                    li += 1
                else:
                    index[i] = work[ri]
                    ri += 1
        length <<= 1
    return index





def main():
    n = int(input())
    AB = np.fromstring(sys.stdin.read(), np.int64, sep=' ').reshape(2, -1).T
    x = 1
    ans = 0
    mod = 1_000_000_007
    idx = argsort(AB)
    AB = AB[idx]
    for i in range(n):
        a, b = AB[i]
        ans += a * x
        ans %= mod
        x *= b
        x %= mod
    print(ans)
    
    

if __name__ == '__main__':
    main()