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;

public class Main{
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int H = scan.nextInt();
		int W = scan.nextInt();
		int[][]a = new int[H][W];
		int cnt = 0;
		for(int i = 0; i < H; i++) {
			for(int j = 0; j < W; j++) {
				int t = scan.nextInt();
				a[i][j] = t;
				if(t % 2 == 1) {
					cnt++;
				}
			}
		}
		scan.close();
		StringBuilder sb = new StringBuilder();
		int[][] list = new int[H * W][2];
		int[] list2 = new int[cnt];
		int index = 0;
		int cnt2 = 0;
		for(int i = 0; i < H; i++) {
			for(int j = 0; j < W; j++) {
				int k = 0;
				if(i % 2 == 1) {
					k = W - j - 1;
				}else {
					k = j;
				}
				if(a[i][k] % 2 == 1) {
					list2[cnt2] = index;
					cnt2 ++;
				}
				list[index][0] = i;
				list[index][1] = k;
				index++;
			}
		}
		int l = cnt;
		if(cnt % 2 == 1) {
			l --;
		}
		int n = 0;
		for(int i = 0; i < l; i+=2) {
			for(int j = list2[i]; j < list2[i+1]; j++) {
				int a1 = list[j][0] + 1;
				int a2 = list[j][1] + 1;
				int a3 = list[j+1][0] + 1;
				int a4 = list[j+1][1] + 1;
				sb.append(a1 + " " + a2 + " " + a3 + " " + a4);
				sb.append("\n");
				n++;
			}
		}
		System.out.println(n);
		System.out.println(sb.toString());

	}

}