private static long [ ] [ ] Combination_nCk ( long n , long k ) {
  n ++ ;
  k ++ ;
  long [ ] [ ] ans = new long [ ( int ) n ] [ ( int ) k ] ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    ans [ i ] [ 0 ] = 1 ;
  }
  for ( int i = 0 ;
  i < n - 1 ;
  i ++ ) {
    for ( int j = 0 ;
    j < k - 1 ;
    j ++ ) {
      if ( i < j ) {
        ans [ i ] [ j ] = 0 ;
      }
      else {
        ans [ i + 1 ] [ j + 1 ] = ans [ i ] [ j ] + ans [ i ] [ j + 1 ] ;
      }
    }
  }
  return ans ;
}

private static long [ ] [ ] Combination_nCk ( long n , long k ) { n ++ ; k ++ ; long [ ] [ ] ans = new long [ ( int ) n ] [ ( int ) k ] ; for ( int i = 0 ; i < n ; i ++ ) { ans [ i ] [ 0 ] = 1 ; } for ( int i = 0 ; i < n - 1 ; i ++ ) { for ( int j = 0 ; j < k - 1 ; j ++ ) { if ( i < j ) { ans [ i ] [ j ] = 0 ; } else { ans [ i + 1 ] [ j + 1 ] = ans [ i ] [ j ] + ans [ i ] [ j + 1 ] ; } } } return ans ; }
(method_declaration (modifiers) type: (array_type element: (integral_type) dimensions: (dimensions)) name: (identifier) parameters: (formal_parameters (formal_parameter type: (integral_type) name: (identifier)) (formal_parameter type: (integral_type) name: (identifier))) body: (block (expression_statement (update_expression (identifier))) (expression_statement (update_expression (identifier))) (local_variable_declaration type: (array_type element: (integral_type) dimensions: (dimensions)) declarator: (variable_declarator name: (identifier) value: (array_creation_expression type: (integral_type) dimensions: (dimensions_expr (cast_expression type: (integral_type) value: (identifier))) dimensions: (dimensions_expr (cast_expression type: (integral_type) value: (identifier)))))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (identifier)) update: (update_expression (identifier)) body: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (decimal_integer_literal)) right: (decimal_integer_literal))))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (binary_expression left: (identifier) right: (decimal_integer_literal))) update: (update_expression (identifier)) body: (block (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (binary_expression left: (identifier) right: (decimal_integer_literal))) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (identifier))) consequence: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (identifier)) right: (decimal_integer_literal)))) alternative: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) right: (binary_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (identifier)) right: (array_access array: (array_access array: (identifier) index: (identifier)) index: (binary_expression left: (identifier) right: (decimal_integer_literal)))))))))))) (return_statement (identifier))))