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Description

0,1,…,n−1 这 n 个数字 (n>1) 排成一个圆圈，从数字 0 开始每次从这个圆圈里删除第 m 个数字。 求出这个圆圈里剩下的最后一个数字。

Input

输入n，m

Output

输出最后一个数字

Samples

5 3

3

Limitation

1s, 1024KiB for each test case.