Problem: This is the easy version of the problem. The difference between the versions is in the number of possible operations that can be made. You can make hacks if and only if you solved both versions of the problem.

You are given a binary table of size n × m. This table consists of symbols 0 and 1.

You can make such operation: select 3 different cells that belong to one 2 × 2 square and change the symbols in these cells (change 0 to 1 and 1 to 0).

Your task is to make all symbols in the table equal to 0. You are allowed to make at most 3nm operations. You don't need to minimize the number of operations.

It can be proved that it is always possible.

Input

The first line contains a single integer t (1 ≤ t ≤ 5000) — the number of test cases. The next lines contain descriptions of test cases.

The first line of the description of each test case contains two integers n, m (2 ≤ n, m ≤ 100).

Each of the next n lines contains a binary string of length m, describing the symbols of the next row of the table.

It is guaranteed that the sum of nm for all test cases does not exceed 20000.

Output

For each test case print the integer k (0 ≤ k ≤ 3nm) — the number of operations.

In the each of the next k lines print 6 integers x_1, y_1, x_2, y_2, x_3, y_3 (1 ≤ x_1, x_2, x_3 ≤ n, 1 ≤ y_1, y_2, y_3 ≤ m) describing the next operation. This operation will be made with three cells (x_1, y_1), (x_2, y_2), (x_3, y_3). These three cells should be different. These three cells should belong into some 2 × 2 square.

Example

Input


5
2 2
10
11
3 3
011
101
110
4 4
1111
0110
0110
1111
5 5
01011
11001
00010
11011
10000
2 3
011
101


Output


1
1 1 2 1 2 2
2 
2 1 3 1 3 2
1 2 1 3 2 3
4
1 1 1 2 2 2 
1 3 1 4 2 3
3 2 4 1 4 2
3 3 4 3 4 4
4
1 2 2 1 2 2 
1 4 1 5 2 5 
4 1 4 2 5 1
4 4 4 5 3 4
2
1 3 2 2 2 3
1 2 2 1 2 2

Note

In the first test case, it is possible to make only one operation with cells (1, 1), (2, 1), (2, 2). After that, all symbols will be equal to 0.

In the second test case:

  * operation with cells (2, 1), (3, 1), (3, 2). After it the table will be: 
    
          
    011  
    001  
    000  
    

  * operation with cells (1, 2), (1, 3), (2, 3). After it the table will be: 
    
          
    000  
    000  
    000  
    




In the fifth test case:

  * operation with cells (1, 3), (2, 2), (2, 3). After it the table will be: 
    
          
    010  
    110  
    

  * operation with cells (1, 2), (2, 1), (2, 2). After it the table will be: 
    
          
    000  
    000  
    

Solution (in JAVA):

Solution:
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.List;
import java.util.Arrays;
import java.util.InputMismatchException;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;

/**
 * Built using CHelper plug-in Actual solution is at the top
 *
 * @author MaxHeap
 */
public class Main {

  public static void main(String[] args) {
    InputStream inputStream = System.in;
    OutputStream outputStream = System.out;
    InputReader in = new InputReader(inputStream);
    PrintWriter out = new PrintWriter(outputStream);
    C2BinaryTableHardVersion solver = new C2BinaryTableHardVersion();
    int testCount = Integer.parseInt(in.next());
    for (int i = 1; i <= testCount; i++) {
      solver.solve(i, in, out);
    }
    out.close();
  }

  static class C2BinaryTableHardVersion {

    List<int[]> ops = new ArrayList<>();
    char[][] mat;

    boolean matches(int[][] cur, int[] v) {
      for (int i = 0; i < 2; ++i) {
        for (int j = 0; j < 2; ++j) {
          if (cur[i][j] != v[i * 2 + j]) {
            return false;
          }
        }
      }
      return true;
    }

    int transform(int[][] cur, int x, int y) {
      int count = 0;
      for (int i = 0; i < 2; ++i) {
        for (int j = 0; j < 2; ++j) {
          if (cur[i][j] == 1) {
            ++count;
          }
        }
      }
      if (count == 0) {
        return 0;
      }
      if (count == 3) {
        int[] res = new int[6];
        int pt = 0;
        for (int i = 0; i < 2; ++i) {
          for (int j = 0; j < 2; ++j) {
            if (cur[i][j] == 1) {
              res[pt++] = x + i;
              res[pt++] = y + j;
            }
          }
        }
        for (int i = 0; i < 2; ++i) {
          for (int j = 0; j < 2; ++j) {
            mat[i + x - 1][y + j - 1] = '0';
          }
        }
        ops.add(res);
        return 1;
      }

      for (int i = 0; i < 2; ++i) {
        for (int j = 0; j < 2; ++j) {
          mat[i + x - 1][y + j - 1] = '0';
        }
      }
      if (matches(cur, new int[]{0, 1, 1, 0})) {
        ops.add(new int[]{x, y, x + 1, y, x + 1, y + 1});
        ops.add(new int[]{x, y, x, y + 1, x + 1, y + 1});
        return 2;
      }
      if (matches(cur, new int[]{1, 0, 0, 1})) {
        ops.add(new int[]{x, y, x + 1, y, x, y + 1});
        ops.add(new int[]{x + 1, y, x, y + 1, x + 1, y + 1});
        return 2;
      }
      if (matches(cur, new int[]{0, 0, 1, 1})) {
        ops.add(new int[]{x, y, x, y + 1, x + 1, y + 1});
        ops.add(new int[]{x, y, x + 1, y, x, y + 1});
        return 2;
      }
      if (matches(cur, new int[]{1, 1, 0, 0})) {
        ops.add(new int[]{x, y + 1, x + 1, y, x + 1, y + 1});
        ops.add(new int[]{x, y, x + 1, y, x + 1, y + 1});
        return 2;
      }
      if (matches(cur, new int[]{1, 0, 1, 0})) {
        ops.add(new int[]{x, y + 1, x + 1, y, x + 1, y + 1});
        ops.add(new int[]{x, y, x, y + 1, x + 1, y + 1});
        return 2;
      }
      if (matches(cur, new int[]{0, 1, 0, 1})) {
        ops.add(new int[]{x, y, x + 1, y, x, y + 1});
        ops.add(new int[]{x, y, x + 1, y, x + 1, y + 1});
        return 2;
      }
      if (matches(cur, new int[]{1, 0, 0, 0})) {
        ops.add(new int[]{x, y, x + 1, y, x, y + 1});
        ops.add(new int[]{x, y, x + 1, y, x + 1, y + 1});
        ops.add(new int[]{x, y, x, y + 1, x + 1, y + 1});
        return 3;
      }
      if (matches(cur, new int[]{0, 1, 0, 0})) {
        ops.add(new int[]{x, y, x, y + 1, x + 1, y + 1});
        ops.add(new int[]{x, y, x + 1, y, x, y + 1});
        ops.add(new int[]{x + 1, y, x, y + 1, x + 1, y + 1});
        return 3;
      }
      if (matches(cur, new int[]{0, 0, 1, 0})) {
        ops.add(new int[]{x, y, x + 1, y, x + 1, y + 1});
        ops.add(new int[]{x, y + 1, x + 1, y, x + 1, y + 1});
        ops.add(new int[]{x, y, x, y + 1, x + 1, y});
        return 3;
      }
      if (matches(cur, new int[]{0, 0, 0, 1})) {
        ops.add(new int[]{x + 1, y + 1, x + 1, y, x, y + 1});
        ops.add(new int[]{x, y, x + 1, y, x + 1, y + 1});
        ops.add(new int[]{x, y, x, y + 1, x + 1, y + 1});
        return 3;
      }

      if (matches(cur, new int[]{1, 1, 1, 1})) {
        ops.add(new int[]{x, y, x + 1, y, x, y + 1});
        ops.add(new int[]{x + 1, y + 1, x + 1, y, x, y + 1});
        ops.add(new int[]{x, y, x + 1, y, x + 1, y + 1});
        ops.add(new int[]{x, y, x, y + 1, x + 1, y + 1});
        return 4;
      }
      throw new RuntimeException("Unknown shape " + Arrays.deepToString(cur));
    }

    public void solve(int testNumber, InputReader in, PrintWriter out) {
      ops.clear();
      int n = in.nextInt(), m = in.nextInt();
      mat = in.nextCharMatrix(n, m);
      int ans = 0;
      for (int i = 0; i + 1 < n; ) {
        for (int j = 0; j + 1 < m; ) {
          int[][] cur = new int[2][2];
          cur[0][0] = mat[i][j] - '0';
          cur[1][0] = mat[i + 1][j] - '0';
          cur[0][1] = mat[i][j + 1] - '0';
          cur[1][1] = mat[i + 1][j + 1] - '0';
          int t = transform(cur, i + 1, j + 1);
          if (j + 2 < m) {
            j += 2;
          } else {
            j += 1;
          }
        }
        if (i + 2 < n) {
          i += 2;
        } else {
          i += 1;
        }
      }
      for (int i = 0; i + 1 < n; i += 1) {
        for (int j = 0; j + 1 < m; j += 1) {
          int[][] cur = new int[2][2];
          cur[0][0] = mat[i][j] - '0';
          cur[1][0] = mat[i + 1][j] - '0';
          cur[0][1] = mat[i][j + 1] - '0';
          cur[1][1] = mat[i + 1][j + 1] - '0';
          int t = transform(cur, i + 1, j + 1);
        }
      }
      out.println(ops.size());
      if (ops.size() > 3 * (n * m)) {
        throw new RuntimeException(testNumber + " n " + (n * m) + " " + ops.size());
      }
      for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
          Checks.verify(mat[i][j] == '0');
        }
      }
      for (int[] op : ops) {
        Printer.print(out, op);
        out.println();
      }
    }

  }

  static final class Checks {

    public static void verify(boolean condition) {
      if (!condition) {
        throw new Checks.InvariantException("Condition not met");
      }
    }

    static class InvariantException extends RuntimeException {

      public InvariantException(String message) {
        super(message);
      }

    }

  }

  static class Printer {

    public static void print(PrintWriter out, int[] arr) {
      print(out, arr, ' ');
    }

    public static void print(PrintWriter out, int[] arr, char sep) {
      for (int i = 0; i < arr.length; ++i) {
        if (i > 0) {
          out.print(sep);
        }
        out.print(arr[i]);
      }
    }

  }

  static class InputReader {

    private InputStream stream;
    private static final int DEFAULT_BUFFER_SIZE = 1 << 16;
    private static final int EOF = -1;
    private byte[] buf = new byte[DEFAULT_BUFFER_SIZE];
    private int curChar;
    private int numChars;

    public InputReader(InputStream stream) {
      this.stream = stream;
    }

    public int read() {
      if (this.numChars == EOF) {
        throw new UnknownError();
      } else {
        if (this.curChar >= this.numChars) {
          this.curChar = 0;

          try {
            this.numChars = this.stream.read(this.buf);
          } catch (IOException ex) {
            throw new InputMismatchException();
          }

          if (this.numChars <= 0) {
            return EOF;
          }
        }

        return this.buf[this.curChar++];
      }
    }

    public int nextInt() {
      int c;
      for (c = this.read(); isSpaceChar(c); c = this.read()) {
      }

      byte sgn = 1;
      if (c == 45) {
        sgn = -1;
        c = this.read();
      }

      int res = 0;

      while (c >= 48 && c <= 57) {
        res *= 10;
        res += c - 48;
        c = this.read();
        if (isSpaceChar(c)) {
          return res * sgn;
        }
      }

      throw new InputMismatchException();
    }

    public String next() {
      int c;
      while (isSpaceChar(c = this.read())) {
      }

      StringBuilder result = new StringBuilder();
      result.appendCodePoint(c);

      while (!isSpaceChar(c = this.read())) {
        result.appendCodePoint(c);
      }

      return result.toString();
    }

    public static boolean isSpaceChar(int c) {
      return c == 32 || c == 10 || c == 13 || c == 9 || c == EOF;
    }

    public char[] nextCharArray() {
      return next().toCharArray();
    }

    public char[][] nextCharMatrix(int n, int m) {
      char[][] res = new char[n][m];
      for (int i = 0; i < n; ++i) {
        res[i] = nextCharArray();
      }
      return res;
    }

  }
}