text: Bottom Left corner of Matrix ( order ( parseInt ( n / 4 ) ) * ( parseInt ( n / 4 ) ) )
code: for ( i = 3 * parseInt ( n / 4 ) ; i < n ; i ++ ) for ( j = 0 ; j < parseInt ( n / 4 ) ; j ++ ) arr [ i ] [ j ] = ( n * n + 1 ) - arr [ i ] [ j ] ;