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.Scanner;

class Main{
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		int H=sc.nextInt();
		int W=sc.nextInt();
		int[][] masu=new int[H][W];
		int[][] buri=new int[H*W][4];
		int b_c=0;

		for(int i=0; i<H; i++) {
			for(int j=0; j<W; j++) {
				masu[i][j]=sc.nextInt();
			}
		}
		int muki=1;

		for(int i=0; i<H; i++) {
			for(int j=0; j<W-1; j++) {
				if(muki==1) {
					if(masu[i][j]%2==1) {
						masu[i][j+1]++;
						masu[i][j]--;
						buri[b_c][0]=i+1;
						buri[b_c][1]=j+1;
						buri[b_c][2]=i+1;
						buri[b_c][3]=j+2;
						b_c++;
					}
					else {
						//
					}
				}

				else if(muki==-1) {
					if(masu[i][W-1-j]%2==1) {
						masu[i][W-j-2]++;
						masu[i][W-j-1]--;
						buri[b_c][0]=i+1;
						buri[b_c][1]=W-j;
						buri[b_c][2]=i+1;
						buri[b_c][3]=W-j-1;
						b_c++;
					}
					else {
						//
					}
				}
			}
			if(i<H-1 && muki==1) {
				if(masu[i][W-1]%2==1) {
					masu[i][W-1]--;
					masu[i+1][W-1]++;
					buri[b_c][0]=i+1;
					buri[b_c][1]=W;
					buri[b_c][2]=i+2;
					buri[b_c][3]=W;
					b_c++;
				}
				muki*=-1;
			}

			else if(i<H-1 && muki==-1) {
				if(masu[i][0]%2==1) {
					masu[i][0]--;
					masu[i+1][0]++;
					buri[b_c][0]=i+1;
					buri[b_c][1]=1;
					buri[b_c][2]=i+2;
					buri[b_c][3]=1;
					b_c++;
				}
				muki*=-1;
			}
		}
		System.out.println(b_c);
		for(int i=0; i<b_c; i++) {
			System.out.println(buri[i][0]+" "+buri[i][1]+" "+buri[i][2]+" "+buri[i][3]);
		}
	}
}