static int NumberOfWays ( int n , int x , int y ) {
  return nCr ( 2 * n - x - y , n - x ) * factorial ( n ) * factorial ( n ) ;
}

static int NumberOfWays ( int n , int x , int y ) { return nCr ( 2 * n - x - y , n - x ) * factorial ( n ) * factorial ( n ) ; }
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