#!/bin/python

import sys
def GCD(a, b):


    if b == 0:
        return a
    else:
        return GCD(b, a % b)
    
def gcd(arr):
    return reduce(GCD, (arr))

def sol(a):
    g = gcd(a)
    s = sum(a)
    m = max(a)
    
    return (g*(s-m))

def maximumValue(a):
    # Return the maximum value of f among all subsegments [l..r].
    max = 0
    
    for i in range(0,len(a)):
        for j in range(i+1,len(a)):
            temp = a[i:j]
            for e in range(0,len(temp)):
                temp[e] = abs(temp[e])
            ans = sol(temp)
            
            if ans > max:
                max = ans
    return max
            


if __name__ == "__main__":
    n = int(raw_input().strip())
    a = map(int, raw_input().strip().split(' '))
    result = maximumValue(a)
    print result