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A. K-Periodic Array

time limit per test

1 secondmemory limit per test

256 megabytesinput

standard inputoutput

standard outputThis task will exclusively concentrate only on the arrays where all elements equal 1 and/or 2.

Array *a* is *k*-period if its length is divisible by *k* and there is such array *b* of length *k*, that *a* is represented by array *b* written exactly times consecutively. In other words, array *a* is *k*-periodic, if it has period of length *k*.

For example, any array is *n*-periodic, where *n* is the array length. Array [2, 1, 2, 1, 2, 1] is at the same time 2-periodic and 6-periodic and array [1, 2, 1, 1, 2, 1, 1, 2, 1] is at the same time 3-periodic and 9-periodic.

For the given array *a*, consisting only of numbers one and two, find the minimum number of elements to change to make the array *k*-periodic. If the array already is *k*-periodic, then the required value equals 0.

Input

The first line of the input contains a pair of integers *n*, *k* (1 ≤ *k* ≤ *n* ≤ 100), where *n* is the length of the array and the value *n* is divisible by *k*. The second line contains the sequence of elements of the given array *a*_{1}, *a*_{2}, ..., *a*_{n} (1 ≤ *a*_{i} ≤ 2), *a*_{i} is the *i*-th element of the array.

Output

Print the minimum number of array elements we need to change to make the array *k*-periodic. If the array already is *k*-periodic, then print 0.

Examples

Input

6 2

2 1 2 2 2 1

Output

1

Input

8 4

1 1 2 1 1 1 2 1

Output

0

Input

9 3

2 1 1 1 2 1 1 1 2

Output

3

Note

In the first sample it is enough to change the fourth element from 2 to 1, then the array changes to [2, 1, 2, 1, 2, 1].

In the second sample, the given array already is 4-periodic.

In the third sample it is enough to replace each occurrence of number two by number one. In this case the array will look as [1, 1, 1, 1, 1, 1, 1, 1, 1] — this array is simultaneously 1-, 3- and 9-periodic.

Codeforces (c) Copyright 2010-2017 Mike Mirzayanov

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