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 sc = new Scanner(System.in);
        int h = sc.nextInt();
        int w = sc.nextInt();
        int[][] a = new int[h+1][w+1];
        for (int i = 1; i <= h; i++) {
            for (int j = 1; j <= w; j++) {
                a[i][j] = sc.nextInt();
            }
        }
        StringBuilder ans = new StringBuilder();
        StringBuilder tmp = new StringBuilder();
        boolean move = false;
        int dir = 1;
        int prex = 1;
        int prey = 0;
        int cnt = 0;
        int tmpCnt = 0;
        for (int i = 1; i <= h; i++) {
            for (int j = 1; j <= w; j++) {
                int x = dir < 0 ? w - j + 1 : j;
                if(!move){
                    if(a[i][x] % 2 != 0){
                        move = true;
                    }
                }else{
                    tmp.append(prey + " " + prex + " " + i + " " + x + "\n");
                    tmpCnt++;
                    if(a[i][x] % 2 != 0){
                        ans.append(tmp.toString());
                        tmp = new StringBuilder();
                        move = false;
                        cnt += tmpCnt;
                        tmpCnt = 0;
                    }
                }
                prey = i;
                prex = x;
            }
            dir *= -1;
        }
        System.out.println(cnt);
        System.out.print(ans.toString());

        sc.close();
    }

}