CF31A.Worms Evolution

Professor Vasechkin is studying evolution of worms. Recently he put forward hypotheses that all worms evolve by division. There are n forms of worms. Worms of these forms have lengths _a_1, _a_2, ..., a__n. To prove his theory, professor needs to find 3 different forms that the length of the first form is equal to sum of lengths of the other two forms. Help him to do this.

瓦谢金教授正在研究蠕虫的进化。最近，他提出了一个假说：所有蠕虫都通过分裂而进化。目前已知存在 $n$ 种蠕虫形态，这些形态的蠕虫长度分别为 $a_1, a_2, \dots, a_n$。为了验证该理论，教授需要找出三种互不相同的形态，使得其中一种形态的长度等于另外两种形态长度之和。请帮助他完成这一任务。

The first line contains integer n (3 ≤ n ≤ 100) — amount of worm's forms. The second line contains n space-separated integers a__i (1 ≤ a__i ≤ 1000) — lengths of worms of each form.

第一行包含一个整数 $n$（$3 \leq n \leq 100$）—— 虫子形态的数量。
第二行包含 $n$ 个用空格分隔的整数 $a_i$（$1 \leq a_i \leq 1000$）—— 每种形态下虫子的长度。

Output 3 distinct integers i j k (1 ≤ i, j, k ≤ n) — such indexes of worm's forms that a__i = a__j + a__k. If there is no such triple, output -1. If there are several solutions, output any of them. It possible that a__j = a__k.

输出三个互不相同的整数 $i$、$j$、$k$（满足 $1 \le i,\,j,\,k \le n$），使得蠕虫的这三种形态满足 $a_i = a_j + a_k$。若不存在这样的三元组，则输出 $-1$。若存在多个解，输出任意一个即可。注意，允许 $a_j = a_k$。