Given S, a set of integers, find the largest d such that a+b+c = d where a, b, c, and d are distinct elements of S. Input Several S, each consisting of a line containing an integer 1 ≤ n ≤ 1000 indicating the number of elements in S, followed by the elements of S, one per line. Each element of S is a distinct integer between -536870912 and +536870911 inclusive. The last line of input contains ‘0’. Output For each S, a single line containing d, or a single line containing ‘no solution’. Sample Input 5 2 3 5 7 12 5 2 16 64 256 1024 0 Sample Output 12 no solution