#D222. Diverse Permutation
Diverse Permutation
Diverse Permutation
Permutation p is an ordered set of integers p1, p2, ..., pn, consisting of n distinct positive integers not larger than n. We'll denote as n the length of permutation p1, p2, ..., pn.
Your task is to find such permutation p of length n, that the group of numbers |p1 - p2|, |p2 - p3|, ..., |pn - 1 - pn| has exactly k distinct elements.
Input
The single line of the input contains two space-separated positive integers n, k (1 ≤ k < n ≤ 105).
Output
Print n integers forming the permutation. If there are multiple answers, print any of them.
Examples
Input
3 2
Output
1 3 2
Input
3 1
Output
1 2 3
Input
5 2
Output
1 3 2 4 5
Note
By |x| we denote the absolute value of number x.
inputFormat
Input
The single line of the input contains two space-separated positive integers n, k (1 ≤ k < n ≤ 105).
outputFormat
Output
Print n integers forming the permutation. If there are multiple answers, print any of them.
Examples
Input
3 2
Output
1 3 2
Input
3 1
Output
1 2 3
Input
5 2
Output
1 3 2 4 5
Note
By |x| we denote the absolute value of number x.
样例
5 2
1 3 2 4 5
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