You are given a garland consisting of n lamps. States of the lamps are represented by the string s of length n. The i-th character of the string s_i equals '0' if the i-th lamp is turned off or '1' if the i-th lamp is turned on. You are also given a positive integer k.

In one move, you can choose one lamp and change its state (i.e. turn it on if it is turned off and vice versa).

The garland is called k-periodic if the distance between each pair of adjacent turned on lamps is exactly k. Consider the case k=3. Then garlands "00010010", "1001001", "00010" and "0" are good but garlands "00101001", "1000001" and "01001100" are not. Note that the garland is not cyclic, i.e. the first turned on lamp is not going after the last turned on lamp and vice versa.

Your task is to find the minimum number of moves you need to make to obtain k-periodic garland from the given one.

You have to answer t independent test cases.

Input

The first line of the input contains one integer t (1 ≤ t ≤ 25~ 000) — the number of test cases. Then t test cases follow.

The first line of the test case contains two integers n and k (1 ≤ n ≤ 10^6; 1 ≤ k ≤ n) — the length of s and the required period. The second line of the test case contains the string s consisting of n characters '0' and '1'.

It is guaranteed that the sum of n over all test cases does not exceed 10^6 (∑ n ≤ 10^6).

Output

For each test case, print the answer — the minimum number of moves you need to make to obtain k-periodic garland from the given one.

Example

Input


6
9 2
010001010
9 3
111100000
7 4
1111111
10 3
1001110101
1 1
1
1 1
0


Output


1
2
5
4
0
0
/*
    Author: Anthony Ngene
    Created: 07/08/2020 - 07:49
*/

import java.io.*;
import java.util.*;

public class E {
// Light travels faster than sound. This is why some people appear bright until you hear them speak. - Alan Dundes
public static void main(String[] args) throws IOException {
    in = new FastScanner();

    int cases = in.intNext();
    for (int t = 1; t <= cases; t++) {
        int n = in.intNext(), k = in.intNext();
        String seq = in.next();
        int[] prefix = new int[n + 1];
        for (int i = 0; i < n; i++) {
            int num = seq.charAt(i) == '1' ? 1 : 0;
            prefix[i + 1] = prefix[i] + num;
        }
        int[] onArr = new int[n + 1];
        int[] offArr = new int[n + 1];
        for (int i = 1; i < n + 1; i++) {
            if (seq.charAt(i - 1) == '1') {
                // turn off
                int off = min(onArr[i - 1], offArr[i - 1]) + 1;
                offArr[i] = off;
                // leave on (set last k to 0)
                int idx = max(i - k, 0);
                int on = prefix[i - 1] - prefix[idx] + onArr[idx];
                on = min(on, prefix[i - 1] - prefix[0]);
                onArr[i] = on;
            } else {
                // keep off
                int off = min(onArr[i - 1], offArr[i - 1]);
                offArr[i] = off;
                // turn on (set last k to 0)
                int idx = max(i - k, 0);
                int on = prefix[i - 1] - prefix[idx] + onArr[idx] + 1;
                on = min(on, prefix[i - 1] - prefix[0]);
                onArr[i] = on;
            }
        }
//        u.print(onArr);
//        u.print(offArr);
        out.println(min(onArr[n], offArr[n]));
    }

    out.close();
}



private static final FastWriter out = new FastWriter();
private static FastScanner in;
static ArrayList<Integer>[] adj;
private static long e97 = (long)1e9 + 7;
static class FastWriter {
    private static final int IO_BUFFERS = 128 * 1024;
    private final StringBuilder out;
    public FastWriter() {
        out = new StringBuilder(IO_BUFFERS);
    }
    public FastWriter p(Object object) {
        out.append(object);
        return this;
    }
    public FastWriter p(String format, Object... args) {
        out.append(String.format(format, args));
        return this;
    }
    public FastWriter pp(Object... args) {
        for (Object ob : args) {
            out.append(ob).append(" ");
        }
        out.append("\n");
        return this;
    }
    public FastWriter println(Object object) {
        out.append(object).append("\n");
        return this;
    }
    public void toFile(String fileName) throws IOException {
        BufferedWriter writer = new BufferedWriter(new FileWriter(fileName));
        writer.write(out.toString());
        writer.close();
    }
    public void close() throws IOException {
        System.out.print(out);
    }
}
static class FastScanner {
    private InputStream sin = System.in;
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;
    public FastScanner(){}
    public FastScanner(String filename) throws FileNotFoundException {
        File file = new File(filename);
        sin = new FileInputStream(file);
    }
    private boolean hasNextByte() {
        if (ptr < buflen) {
            return true;
        }else{
            ptr = 0;
            try {
                buflen = sin.read(buffer);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (buflen <= 0) {
                return false;
            }
        }
        return true;
    }
    private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
    private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
    public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
    public String next() {
        if (!hasNext()) throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = readByte();
        while(isPrintableChar(b)) {
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }
    public long longNext() {
        if (!hasNext()) throw new NoSuchElementException();
        long n = 0;
        boolean minus = false;
        int b = readByte();
        if (b == '-') {
            minus = true;
            b = readByte();
        }
        if (b < '0' || '9' < b) {
            throw new NumberFormatException();
        }
        while(true){
            if ('0' <= b && b <= '9') {
                n *= 10;
                n += b - '0';
            }else if(b == -1 || !isPrintableChar(b) || b == ':'){
                return minus ? -n : n;
            }else{
                throw new NumberFormatException();
            }
            b = readByte();
        }
    }
    public int intNext() {
        long nl = longNext();
        if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
        return (int) nl;
    }
    public double doubleNext() { return Double.parseDouble(next());}
    public long[] nextLongArray(final int n){
        final long[] a = new long[n];
        for (int i = 0; i < n; i++)
            a[i] = longNext();
        return a;
    }
    public int[] nextIntArray(final int n){
        final int[] a = new int[n];
        for (int i = 0; i < n; i++)
            a[i] = intNext();
        return a;
    }
    public ArrayList<Integer>[] getAdj(int n) {
        ArrayList<Integer>[] adj = new ArrayList[n + 1];
        for (int i = 1; i <= n; i++) adj[i] = new ArrayList<>();
        return adj;
    }

    public ArrayList<Integer>[] adjacencyList(int n, int m) throws IOException {
        adj = getAdj(n);
        for (int i = 0; i < m; i++) {
            int a = intNext(), b = intNext();
            adj[a].add(b);
            adj[b].add(a);
        }
        return adj;
    }
}
private static int min(int a, int b){   return (a>b) ? b : a;   }
private static int max(int a, int b){   return (a>b) ? a : b;   }
}
