CF253A.Boys and Girls

There are n boys and m girls studying in the class. They should stand in a line so that boys and girls alternated there as much as possible. Let's assume that positions in the line are indexed from left to right by numbers from 1 to n + m. Then the number of integers i (1 ≤ i < n + m) such that positions with indexes i and i + 1 contain children of different genders (position i has a girl and position i + 1 has a boy or vice versa) must be as large as possible.

Help the children and tell them how to form the line.

班上有 $n$ 个男生和 $m$ 个女生。他们需要排成一列，使得男生与女生尽可能多地交替出现。假设队列中的位置从左到右依次用 $1$ 到 $n + m$ 的整数编号，则满足“位置 $i$ 与位置 $i+1$ 上的孩子性别不同”（即位置 $i$ 是女生而位置 $i+1$ 是男生，或位置 $i$ 是男生而位置 $i+1$ 是女生）的整数 $i$ 的个数（其中 $1 \leq i < n + m$）应尽可能大。

请帮助孩子们，告诉他们该如何排成这一队列。

The single line of the input contains two integers n and m (1 ≤ n, m ≤ 100), separated by a space.

输入仅包含一行，其中有两个整数 $n$ 和 $m$（$1 ≤ n, m ≤ 100$），用空格分隔。

Print a line of n + m characters. Print on the i-th position of the line character "B", if the i-th position of your arrangement should have a boy and "G", if it should have a girl.

Of course, the number of characters "B" should equal n and the number of characters "G" should equal m. If there are multiple optimal solutions, print any of them.

输出一行包含 $n + m$ 个字符的字符串。若你所安排的序列中第 $i$ 个位置应为男孩，则在该行第 $i$ 个位置输出字符 "B"；若应为女孩，则输出 "G"。

显然，字符 "B" 的个数应恰好为 $n$，字符 "G" 的个数应恰好为 $m$。若存在多个最优解，输出任意一个即可。

In the first sample another possible answer is BGBGBG.

In the second sample answer BBGBGB is also optimal.

在第一个样例中，另一个可能的答案是 BGBGBG。

在第二个样例中，答案 BBGBGB 同样是最优的。