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.*;
import java.util.StringTokenizer;
import java.util.ArrayList;

class Main {
    static class InputReader {
        BufferedReader br;
        StringTokenizer st;
        public InputReader(){
            br = new BufferedReader(new InputStreamReader(System.in));
        }
        String next(){
            while (st == null || !st.hasMoreElements()){
                try{
                    st = new StringTokenizer(br.readLine());
                }
                catch (IOException e){
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }
        int nextInt(){
            return Integer.parseInt(next());
        }
        long nextLong(){
            return Long.parseLong(next());
        }
        double nextDouble() {
            return Double.parseDouble(next());
        }
        String nextLine(){
            String str = "";
            try{
                str = br.readLine();
            }
            catch(IOException e){
                e.printStackTrace();
            }
            return str;
        }
    }
    static class Move{
        public Move(int i1, int j1){
            this.i1 = i1; this.j1 = j1;
        }
        public int i1, j1, i2, j2;
        public String toString(){
            return String.format("%d %d %d %d%n", i1+1, j1+1, i2+1, j2+1);
        }
    }

    public static void main(String[] args) throws IOException {
        InputReader in = new InputReader();
        BufferedWriter out =  new BufferedWriter(new OutputStreamWriter(System.out));

        int H = in.nextInt(), W = in.nextInt();
        int[][] matrix = new int[H][W];
        for (int i = 0; i < H; ++i) {
            for (int j = 0; j < W; ++j) {
                matrix[i][j] = in.nextInt();
            }
        }
        ArrayList<Move> answer = solve(H, W, matrix);
        out.write(answer.size() + "\n");
        for (Move move : answer){
            out.write(move.toString());
        }
        out.flush();
    }
    public static ArrayList<Move> solve(int H, int W, int[][] matrix){
        ArrayList<Move> moves = new ArrayList<>();
        for (int i = 0; i < H; ++i){
            if ((i & 1) == 0) {
                for (int j = 0; j < W; ++j){
                    if ((matrix[i][j] & 1) == 0) continue;
                    Move move = new Move(i, j);
                    matrix[i][j]--;
                    if (j < W - 1){
                        matrix[i][j+1]++;
                        move.i2 = i; move.j2 = j+1;
                        moves.add(move);
                    }
                    else{
                        if (i == H - 1) continue;
                        matrix[i+1][j]++;
                        move.i2 = i+1; move.j2 = j;
                        moves.add(move);
                    }
                }
            }
            else{
                for (int j = W-1; j >= 0; --j){
                    if ((matrix[i][j] & 1) == 0) continue;
                    Move move = new Move(i, j);
                    matrix[i][j]--;
                    if (j > 0){
                        matrix[i][j-1]++;
                        move.i2 = i; move.j2 = j-1;
                        moves.add(move);
                    }
                    else{
                        if (i == H - 1) continue;
                        matrix[i+1][j]++;
                        move.i2 = i+1; move.j2 = j;
                        moves.add(move);
                    }
                }
            }
        }
        return moves;
    }
}