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.* ;
public class Main{
       public static void main( String args[] ){
             Scanner cin = new Scanner( System.in ) ;
             int h = cin.nextInt() ;
             int w = cin.nextInt() ;
             int a[][] = new int[510][510] ;
             for( int i = 1 ; i <= h ; i++ )
                 for( int j = 1 ; j <= w ; j++ )
                     a[i][j] = cin.nextInt() ;
             int cnt = 0 ;
             int x1[] = new int[250010] ;
             int y1[] = new int[250010] ;
             int x2[] = new int[250010] ;
             int y2[] = new int[250010] ;
             for( int i = 1 ; i <= h ; i++ )
                 for( int j = 1 ; j <= w ; j++ ){
                     if ( j < w ){
                         if ( a[i][j] % 2 == 1 ){
                             cnt++ ; 
                             x1[cnt] = i ; y1[cnt] = j ;
                             a[i][j]-- ;
                             a[i][j + 1]++ ;
                             x2[cnt] = i ; y2[cnt] = j + 1 ;
                         }
                     }
                     else{
                         if ( i != h ){
                             if ( a[i][j]  % 2 == 1 ){
                                 cnt++ ;
                                 x1[cnt] = i ; y1[cnt] = j ;
                                 a[i][j]-- ;
                                 a[i + 1][j]++ ;
                                 x2[cnt] = i + 1 ; y2[cnt] = j ;
                             }
                         }
                     }
                 }
            System.out.println( cnt ) ;
            for( int i = 1 ; i <= cnt ; i++ )
                System.out.println( x1[i] + " " + y1[i] + " " + x2[i] + " " + y2[i] ) ;
       }
}