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#include <iostream>
#include <cstdio>
using namespace std;

char tab[ 3001 ][ 3001 ];
int where[ 4 ][ 2 ];

int canI( int x, int y )
{
    if ( tab[ x ][ y ] != '.' ) return 0;
    if ( tab[ x - 1 ][ y ] == '#' || tab[ x + 1 ][ y ] == '#' || tab[ x ][ y - 1 ] == '#' || tab[ x ][ y + 1 ] == '#' ) return 1;
    if ( tab[ x - 1 ][ y ] == '?' || tab[ x + 1 ][ y ] == '?' || tab[ x ][ y - 1 ] == '?' || tab[ x ][ y + 1 ] == '?' ) return 2;
    return 0;
}

bool reallyCanI( int x, int y, int q )
{
    for ( int i = 0; i < q; ++i )
    {
        if ( x < where[ i ][ 0 ] || x == where[ i ][ 0 ] && y < where[ i ][ 1 ] ) return false;
    }
    return true;
}

int fun( int k, int n, int q = 0 )
{
    int h, counter = 0;

    if ( q == k ) return 1;

    for ( int i = 1; i <= n; ++i )
    {
        for ( int j = 1; j <= n; ++j )
        {
            h = canI( i, j );
            if ( h == 1 )
            {
                if ( reallyCanI( i, j, q ) )
                {
                    where[ q ][ 0 ] = i;
                    where[ q ][ 1 ] = j;
                    tab[ i ][ j ] = '?';
                    counter = ( counter + fun( k, n, q + 1 ) ) % 1000000007;
                    tab[ i ][ j ] = '.';
                }
            }
            else if ( h == 2 )
            {
                where[ q ][ 0 ] = i;
                where[ q ][ 1 ] = j;
                tab[ i ][ j ] = '?';
                counter = ( counter + fun( k, n, q + 1 ) ) % 1000000007;
                tab[ i ][ j ] = '.';
            }
        }
    }
    return counter;
}

int main()
{
    int n, k;
    char z;
    scanf( "%d%d%c", &n, &k, &z );

    for ( int i = 1; i <= n; ++i )
    {
        for ( int j = 1; j <= n; ++j )
        {
            scanf( "%c", &tab[ i ][ j ] );
        }
        scanf( "%c", &z );
    }

    printf( "%d\n", fun( k, n ) );
}