public static void main ( String [ ] args ) {
  Scanner s = new Scanner ( System . in ) ;
  String ch = s . next ( ) ;
  String ch1 = "" ;
  String ch2 = "" ;
  boolean aux = true ;
  if ( Character . isLowerCase ( ch . charAt ( 0 ) ) ) {
    for ( int i = 1 ;
    i < ch . length ( ) ;
    i ++ ) {
      if ( Character . isLowerCase ( ch . charAt ( i ) ) ) {
        aux = false ;
        break ;
      }
    }
    if ( aux == false ) {
      System . out . println ( ch ) ;
    }
    else {
      ch1 = ch1 + Character . toUpperCase ( ch . charAt ( 0 ) ) ;
      for ( int i = 1 ;
      i < ch . length ( ) ;
      i ++ ) {
        ch1 = ch1 + Character . toLowerCase ( ch . charAt ( i ) ) ;
      }
      System . out . println ( ch1 ) ;
    }
  }
  else {
    for ( int i = 1 ;
    i < ch . length ( ) ;
    i ++ ) {
      if ( Character . isLowerCase ( ch . charAt ( i ) ) ) {
        aux = false ;
        break ;
      }
    }
    if ( aux == false ) {
      System . out . println ( ch ) ;
    }
    else {
      ch2 = ch2 + Character . toLowerCase ( ch . charAt ( 0 ) ) ;
      for ( int i = 1 ;
      i < ch . length ( ) ;
      i ++ ) {
        ch2 = ch2 + Character . toLowerCase ( ch . charAt ( i ) ) ;
      }
      System . out . println ( ch2 ) ;
    }
  }
}

public static void main ( String [ ] args ) { Scanner s = new Scanner ( System . in ) ; String ch = s . next ( ) ; String ch1 = " " ; String ch2 = " " ; boolean aux = true ; if ( Character . isLowerCase ( ch . charAt ( 0 ) ) ) { for ( int i = 1 ; i < ch . length ( ) ; i ++ ) { if ( Character . isLowerCase ( ch . charAt ( i ) ) ) { aux = false ; break ; } } if ( aux == false ) { System . out . println ( ch ) ; } else { ch1 = ch1 + Character . toUpperCase ( ch . charAt ( 0 ) ) ; for ( int i = 1 ; i < ch . length ( ) ; i ++ ) { ch1 = ch1 + Character . toLowerCase ( ch . charAt ( i ) ) ; } System . out . println ( ch1 ) ; } } else { for ( int i = 1 ; i < ch . length ( ) ; i ++ ) { if ( Character . isLowerCase ( ch . charAt ( i ) ) ) { aux = false ; break ; } } if ( aux == false ) { System . out . println ( ch ) ; } else { ch2 = ch2 + Character . toLowerCase ( ch . charAt ( 0 ) ) ; for ( int i = 1 ; i < ch . length ( ) ; i ++ ) { ch2 = ch2 + Character . toLowerCase ( ch . charAt ( i ) ) ; } System . out . println ( ch2 ) ; } } }
(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 (field_access object: (identifier) field: (identifier)))))) (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (string_literal))) (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (string_literal))) (local_variable_declaration type: (boolean_type) declarator: (variable_declarator name: (identifier) value: (true))) (if_statement condition: (parenthesized_expression (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal)))))) consequence: (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: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))))) consequence: (block (expression_statement (assignment_expression left: (identifier) right: (false))) (break_statement))))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (false))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))) alternative: (block (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (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: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) update: (update_expression (identifier)) body: (block (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))))))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))))) alternative: (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: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))))) consequence: (block (expression_statement (assignment_expression left: (identifier) right: (false))) (break_statement))))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (false))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))) alternative: (block (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (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: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) update: (update_expression (identifier)) body: (block (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))))))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))))))))