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.*;

public class Main {
	public static void main (String[] args) {
		Scanner sc = new Scanner(System.in);
		int h = sc.nextInt();
		int w = sc.nextInt();
		int[][] field = new int[h + 1][w + 1];
		for (int i = 1; i <= h; i++) {
		    for (int j = 1; j <= w; j++) {
		        field[i][j] = sc.nextInt();
		    }
		}
		ArrayList<Graph> list = new ArrayList<>();
		for (int i = 1; i <= h; i++) {
	        for (int j = 1; j < w; j++) {
	            if (field[i][j] % 2 == 1) {
	                field[i][j + 1]++;
	                list.add(new Graph(i, j, i, j + 1));
	            }
	        }
	        if (field[i][w] % 2 == 1 && i < h) {
	            field[i + 1][w]++;
	            list.add(new Graph(i, w, i + 1, w));
	        }
		}
		StringBuilder sb = new StringBuilder();
		sb.append(list.size()).append("\n");
		for (Graph g : list) {
		    sb.append(g);
		}
		System.out.print(sb);
    }
    
    static class Graph {
        int a;
        int b;
        int c;
        int d;
        
        public Graph(int a, int b, int c, int d) {
            this.a = a;
            this.b = b;
            this.c = c;
            this.d = d;
        }
        
        public String toString() {
            return new StringBuilder().append(a).append(" ").append(b).append(" ").append(c).append(" ").append(d).append("\n").toString();
        }
    }
}