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.ArrayList;
import java.util.Scanner;

public class Main {
	static int[][] a;
	static ArrayList<String> ans = new ArrayList<>();
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		final int h = scanner.nextInt();
		final int w = scanner.nextInt();
		a = new int[h][w];
		for (int r=0; r<h; r++){
			for (int c=0; c<w; c++){
				a[r][c] = scanner.nextInt();
			}
		}
		for(int r=0; r<h; r++){
			for (int c=0; c<w; c++){
				int now = a[r][c];
				if(now%2==1){
					int right;
					int down;
					boolean rightEven = true;
					boolean downEven = true;
					if (c!=w-1) {
						right=a[r][c+1];
						rightEven = right%2==0;
					}
					if (r!=h-1) {
						down=a[r+1][c];
						downEven = down%2==0;
					}
					if(rightEven && downEven) {
						if (c!=w-1) move(r,c,r,c+1);	//toRight
						else if (r!=h-1) move(r,c,r+1,c);	//toDown
					}else if (!rightEven) move(r,c,r,c+1);	//toRight
					else move(r,c,r+1,c);	//toDown
				}
			}
		}
		System.out.println(ans.size());
		ans.forEach(System.out::println);
	}

	static void move(int y, int x, int y_, int x_){
		ans.add((y+1)+" "+(x+1)+" "+(y_+1)+" "+(x_+1));
		a[y][x]--;
		a[y_][x_]++;
	}
}