Problem:
Score : 400 points

Problem Statement

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.

Sample Input 1

2 3
1 2 3
0 1 1

Sample Output 1

3
2 2 2 3
1 1 1 2
1 3 1 2

Every cell contains an even number of coins after the following sequence of operations:

Move the coin in Cell (2, 2) to Cell (2, 3).

Move the coin in Cell (1, 1) to Cell (1, 2).

Move one of the coins in Cell (1, 3) to Cell (1, 2).

Sample Input 2

3 2
1 0
2 1
1 0

Sample Output 2

3
1 1 1 2
1 2 2 2
3 1 3 2

Sample Input 3

1 5
9 9 9 9 9

Sample Output 3

2
1 1 1 2
1 3 1 4

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.List;
import java.util.Scanner;
import java.util.ArrayList;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author mikit
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        DMakeThemEven solver = new DMakeThemEven();
        solver.solve(1, in, out);
        out.close();
    }

    static class DMakeThemEven {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            /* == 入力部       開始 == */
            int h = in.nextInt();                           // 盤面の横幅
            int w = in.nextInt();                           // 盤面の縦幅
            List<DMakeThemEven.Operation> operations = new ArrayList<>(); // 解答
            /* == 入力部       開始 == */

            /* == 計算部(1)    開始 == */
            /* vParity[i] = (i + 1,1)要素から(i + 1,y + 1)要素までの和が奇数ならtrue -> コインを下に押し付けます */
            boolean[] vParity = new boolean[w];
            for (int y = 0; y < h - 1; y++) {   // 上から下へ(最終行を除く)
                for (int x = 0; x < w; x++) {   // 左から右へ
                    vParity[x] ^= in.nextInt() % 2 == 1; // 偶奇の和はXORで求まります
                    if (vParity[x]) { // 奇数ならば下の行にコインを押し付けます
                        operations.add(new DMakeThemEven.Operation(x + 1, y + 1, x + 1, y + 2));
                    }
                }
            }
            /* == 計算部(1)    終了 == */


            /* == 計算部(2)    開始 == */
            /* hParity = (x + 1, h)要素が奇数ならtrue -> コインを右に押し付ける */
            boolean hParity = false;
            for (int x = 0; x < w - 1; x++) {   // 左から右へ
                // (x + 1, h)要素の偶奇性は [もともとその場所にあるコイン] XOR [上から押し付けられたコイン]
                //                                                   XOR [左から押し付けられたコイン]
                hParity ^= vParity[x];
                hParity ^= in.nextInt() % 2 == 1;
                if (hParity) { // 奇数ならば右の列にコインを押し付けます
                    operations.add(new DMakeThemEven.Operation(x + 1, h, x + 2, h));
                }
            }
            /* == 計算部(2)    終了 == */


            /* == 出力部    開始 == */
            out.println(operations.size());
            for (DMakeThemEven.Operation operation : operations) {
                out.print(operation.y1);
                out.print(' ');
                out.print(operation.x1);
                out.print(' ');
                out.print(operation.y2);
                out.print(' ');
                out.println(operation.x2);
            }
            /* == 出力部    終了 == */
        }

        public static class Operation {
            int x1;
            int y1;
            int x2;
            int y2;

            public Operation(int a, int b, int c, int d) {
                this.x1 = a;
                this.y1 = b;
                this.x2 = c;
                this.y2 = d;
            }

        }

    }
}