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

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