public static void main ( String [ ] args ) {
  FastScanner scanner = new FastScanner ( ) ;
  int n = scanner . nextInt ( ) ;
  int [ ] arr = new int [ 3009 ] ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    arr [ scanner . nextInt ( ) ] ++ ;
  }
  for ( int i = 1 ;
  i < arr . length ;
  i ++ ) {
    if ( arr [ i ] == 0 ) {
      System . out . println ( i ) ;
      return ;
    }
  }
}

public static void main ( String [ ] args ) { FastScanner scanner = new FastScanner ( ) ; int n = scanner . nextInt ( ) ; int [ ] arr = new int [ 3009 ] ; for ( int i = 0 ; i < n ; i ++ ) { arr [ scanner . nextInt ( ) ] ++ ; } for ( int i = 1 ; i < arr . length ; i ++ ) { if ( arr [ i ] == 0 ) { System . out . println ( i ) ; return ; } } }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (array_type element: (type_identifier) dimensions: (dimensions)) name: (identifier))) body: (block (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (type_identifier) arguments: (argument_list)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (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 (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: (identifier)) update: (update_expression (identifier)) body: (block (expression_statement (update_expression (array_access array: (identifier) index: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))))))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (field_access object: (identifier) field: (identifier))) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (decimal_integer_literal))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier)))) (return_statement)))))))