Problem: There is a grid of square cells with H horizontal rows and W vertical columns. The cell at the i-th row and the j-th column will be denoted as Cell (i, j).

In Cell (i, j), a_{ij} coins are placed.

You can perform the following operation any number of times:

Operation: Choose a cell that was not chosen before and contains one or more coins, then move one of those coins to a vertically or horizontally adjacent cell.

Maximize the number of cells containing an even number of coins.

Constraints

* All values in input are integers.
* 1 \leq H, W \leq 500
* 0 \leq a_{ij} \leq 9

Input

Input is given from Standard Input in the following format:


H W
a_{11} a_{12} ... a_{1W}
a_{21} a_{22} ... a_{2W}
:
a_{H1} a_{H2} ... a_{HW}


Output

Print a sequence of operations that maximizes the number of cells containing an even number of coins, in the following format:


N
y_1 x_1 y_1' x_1'
y_2 x_2 y_2' x_2'
:
y_N x_N y_N' x_N'


That is, in the first line, print an integer N between 0 and H \times W (inclusive), representing the number of operations.

In the (i+1)-th line (1 \leq i \leq N), print four integers y_i, x_i, y_i' and x_i' (1 \leq y_i, y_i' \leq H and 1 \leq x_i, x_i' \leq W), representing the i-th operation. These four integers represents the operation of moving one of the coins placed in Cell (y_i, x_i) to a vertically or horizontally adjacent cell, (y_i', x_i').

Note that if the specified operation violates the specification in the problem statement or the output format is invalid, it will result in Wrong Answer.

Examples

Input

2 3
1 2 3
0 1 1


Output

3
2 2 2 3
1 1 1 2
1 3 1 2


Input

3 2
1 0
2 1
1 0


Output

3
1 1 1 2
1 2 2 2
3 1 3 2


Input

1 5
9 9 9 9 9


Output

2
1 1 1 2
1 3 1 4

Solution (in JAVA):

Solution:
import java.util.*;
import java.awt.*;

public class Main {
  public static void main(String args[]) {
    Scanner sc = new Scanner(System.in);

    int H = sc.nextInt();
    int W = sc.nextInt();
    int[][] a = new int[H][W];
    for (int i = 0; i < H; i++) {
      for (int j = 0; j < W; j++) {
        a[i][j] = sc.nextInt();
      }
    }

    int h = 0;
    int w = 0;
    int true_j = 0;
    int flag = 1;
    int back = 1;
    int[][] ans = new int[H * W][4];
    int count = 0;

    for (int i = 0; i < H; i++) {
      for (int j = 0; j < W; j++) {
        if (back == 1) {
          true_j = j;
        } else {
          true_j = W-1-j;
        }

        int current = a[i][true_j];

        if (flag == 1) {
          if (current % 2 == 1) {
            flag *= -1;
          }
        } else {
          if (current % 2 == 1) {
            flag *= -1;
          }

          ans[count][0] = h+1;
          ans[count][1] = w+1;
          ans[count][2] = i+1;
          ans[count][3] = true_j+1;
          count++;
        }

        h = i;
        w = true_j;
      }

      back *= -1;
    }

    System.out.println(count);
    for (int i = 0; i < count; i++) {
      System.out.println(ans[i][0]+" "+ans[i][1]+" "+ans[i][2]+" "+ans[i][3]);
    }
  }
}