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A11472. Cave Painting

编程题 普及/提高-
知识点

题目描述

Imp is watching a documentary about cave painting.

![](/uploads/acgo/image/bde88a4538254817_3aacfc945117.jpeg)Some numbers, carved in chaotic order, immediately attracted his attention. Imp rapidly proposed a guess that they are the remainders of division of a number $n$ by all integers $i$ from $1$ to $k$ . Unfortunately, there are too many integers to analyze for Imp.

Imp wants you to check whether all these remainders are distinct. Formally, he wants to check, if all ![](/uploads/acgo/image/388cc1615c132ed7_b8baa611a179.jpeg), $1<=i<=k$ , are distinct, i. e. there is no such pair $(i,j)$ that:

- $1 \leq i < j \leq k$ ,
- ![](/uploads/luogu/CF922C/ac7c31555d5d75a7ddeca570475f6120983c1d66_945869ce6e34.png), where ![](/uploads/acgo/image/8835a27172590ed8_d0031680473e.jpeg) is the remainder of division $x$ by $y$ .

输入格式

The only line contains two integers $n$ , $k$ $(1<=n,k<=10^{18})$ .

输出格式

Print "Yes", if all the remainders are distinct, and "No" otherwise.

You can print each letter in arbitrary case (lower or upper).

输入输出样例

输入 #1
4 4
输出 #1
No
输入 #2
5 3
输出 #2
Yes

说明/提示

In the first sample remainders modulo $1$ and $4$ coincide.
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