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.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Main {
	private static class Operation {
		public int srcX, srcY, dstX, dstY;

		public Operation(int srcY, int srcX, int dstY, int dstX) {
			this.srcX = srcX;
			this.srcY = srcY;
			this.dstX = dstX;
			this.dstY = dstY;
		}
	}

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		String[] tokens = in.nextLine().split(" ");
		int H = Integer.parseInt(tokens[0]);
		int W = Integer.parseInt(tokens[1]);
		int[][] a = new int[H][W];
		int oddNum = 0;
		for (int i = 0; i < H; ++i) {
			tokens = in.nextLine().split(" ");
			for (int j = 0; j < W; ++j) {
				a[i][j] = Integer.parseInt(tokens[j]);
				if (a[i][j] % 2 == 1) {
					oddNum++;
				}
			}
		}
		List<Operation> operations = new ArrayList<>();
		// 奇数の数が奇数個 -> 1つ残る，偶数個 -> 全部偶数になる
		// でも，全部片寄するのでもいい気がする
		for (int i = 0; i + 1 < H; ++i) {
			for (int j = 0; j < W; ++j) {
				if (a[i][j] % 2 != 0) {
					// 下に1つ移動する
					operations.add(new Operation(i, j, i + 1, j));
					a[i][j]--;
					a[i + 1][j]++;
				}
			}
		}
		for (int j = 0; j + 1 < W; ++j) {
			if (a[H - 1][j] % 2 != 0) {
				// 右に1つ移動する
				operations.add(new Operation(H - 1, j, H - 1, j + 1));
				a[H - 1][j]--;
				a[H - 1][j + 1]++;
			}
		}
		System.out.println(operations.size());
		for (int i = 0; i < operations.size(); ++i) {
			Operation op = operations.get(i);
			System.out.println((op.srcY + 1) + " " + (op.srcX + 1) + " " + (op.dstY + 1) + " " + (op.dstX + 1));
		}

		in.close();
	}
}