# 2961
import sys
import itertools
N = int(sys.stdin.readline())
arr = [list(map(int, sys.stdin.readline().split())) for _ in range(N)]
# ex : [[1,7],[2,6],[3,8],[4,9]]
ans = 1e9
for i in range(1,N+1) : # 조합 개수를 1~N 개까지
combinations = itertools.combinations(arr,i) # ex : [([1,7],[2,6]),([3,8],[4,9])]
for com in combinations : # ex : ([1,7],[2,6])
s , m = 0 , 1
for j in com : # ex : [1,7]
m *= j[0]
s += j[1]
ans = min(ans,abs(s-m))
print(ans)