描述

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.

输入

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.

输出

For each S, a single line containing d, or a single line containing "no solution".

翻译

描述

给出一个数组S，找出数组中最大的d，d=a+b+c，a，b，c，d都是数组S中的元素。

输入

一些数组S，每个由第一行的一个代表该数组元素个数的整数n，以及下面每行一个元素 的n行组成。每个元素都是-536870912和+536870911之间的不同的整数。最后一行输入是0；

输出

对于每一个数组S，输出一行包含d，或是一行"no solution"。