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.io.InputStream;
import java.io.PrintWriter;
import java.lang.reflect.Array;
import java.math.BigDecimal;
import java.math.MathContext;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Scanner;
import java.util.Set;
import java.util.Stack;
import java.util.TreeMap;
import java.util.TreeSet;

import static java.util.Comparator.*;

public class Main {
    public static void main(String[] args) {
        PrintWriter out = new PrintWriter(System.out);
        Solver solver = new Solver(System.in, out);
        solver.solve();
        out.close();
    }
}
class Solver {
	Scanner sc;
	PrintWriter out;
    public Solver(InputStream in, PrintWriter out) {
    	sc = new Scanner(in);
    	this.out = out;
    }
    // ==================================================================
    public void solve() {
    	int H = Integer.parseInt(sc.next());
    	int W = Integer.parseInt(sc.next());
    	int[][] A = new int[H][W];
    	for (int i = 0; i < H; i++) {
    		for (int j = 0; j < W; j++) {
    			A[i][j] = Integer.parseInt(sc.next());
    		}
		}
    	int N = 0;
    	boolean f = true;
    	List<PP> hist = new ArrayList<>();
    	for (int i = 0; i < H; i++) {
			if(f) {
				for (int j = 0; j < W; j++) {
					if(A[i][j] % 2 == 1) {
						if(j != W-1) {
							N++;
							A[i][j+1]++;
							hist.add(new PP(i,j,i,j+1));
						} else if(i != H-1) {
							N++;
							A[i+1][j]++;
							hist.add(new PP(i,j,i+1,j));
						}
					}
				}
			} else {
				for( int j = W-1; j >= 0; j--) {
					if(A[i][j] % 2 == 1) {
						if(j != 0) {
							N++;
							A[i][j-1]++;
							hist.add(new PP(i,j,i,j-1));
						} else if(i != H-1) {
							N++;
							A[i+1][j]++;
							hist.add(new PP(i,j,i+1,j));
						}
					}
				}
			}
			f = !f;
		}
    	out.println(N);
    	for (PP p : hist) {
			out.println((p.y1+1) + " " + (p.x1+1) + " " + (p.y2+1) + " " + (p.x2+1));
		}
    }
    class PP {
    	int y1, x1, y2, x2;
    	public PP(int y1, int x1, int y2, int x2) {
    		this.y1 = y1;
    		this.x1 = x1;
    		this.y2 = y2;
    		this.x2 = x2;
    	}
    }
}