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.List;
import java.util.Scanner;

public class Main{
	
	static int [][]grid;
	static int h,w;
	static List<Point> ans;

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		 h = Integer.parseInt(sc.next());
		 w = Integer.parseInt(sc.next());
		 
		 grid = new int [h+1][w+1];
		 
		 for(int i = 1 ; i <= h ;i++) {
			 for(int j = 1 ; j <= w ; j++) {
				 grid[i][j] = Integer.parseInt(sc.next());
			 }
		 }
		 
		 ans = new ArrayList<Point>();
		 boolean flag = false;
		
		 for(int i = 1 ; i < h ; i++) {
			 for(int j = 1 ; j <= w ; j++) {
				 if(grid[i][j] % 2 == 1) {
					 grid[i+1][j]++;
					 ans.add(new Point(i,j,i+1,j));
				 }
			 }
		 }
		 
		 for(int i = 1 ; i < w ; i++) {
			 if(grid[h][i] % 2 == 1) {
				 ans.add(new Point(h,i,h,i+1));
				 grid[h][i+1]++;
			 }
		}
	
		System.out.println(ans.size());
		for(Point e : ans) {
			System.out.println(e.getY()+" "+e.getX()+" "+e.getYy()+" "+e.getXx());
		}
	}	
}
class Point {
	private int y;
	private int x;
	private int yy;
	private int xx;
	
	public Point (int y, int x , int yy, int xx) {
		this.y = y;
		this.x = x;
		this.yy = yy;
		this.xx = xx;
	}

	public int getY() {
		return y;
	}

	public int getX() {
		return x;
	}

	public int getYy() {
		return yy;
	}

	public int getXx() {
		return xx;
	}
	
	
}