public static void main ( String args [ ] ) {
  Scanner s = new Scanner ( System . in ) ;
  long a = s . nextLong ( ) ;
  long b = s . nextLong ( ) ;
  if ( a == b ) {
    System . out . print ( ( 10 * a ) + " " + ( 10 * b + 1 ) ) ;
    return ;
  }
  if ( a + 1 == b ) {
    System . out . print ( ( 10 * a + 9 ) + " " + ( 10 * b ) ) ;
    return ;
  }
  if ( b == 1 && a == 9 ) {
    System . out . print ( 9 + " " + 10 ) ;
    return ;
  }
  System . out . print ( - 1 ) ;
}

public static void main ( String args [ ] ) { Scanner s = new Scanner ( System . in ) ; long a = s . nextLong ( ) ; long b = s . nextLong ( ) ; if ( a == b ) { System . out . print ( ( 10 * a ) + " ▁ " + ( 10 * b + 1 ) ) ; return ; } if ( a + 1 == b ) { System . out . print ( ( 10 * a + 9 ) + " ▁ " + ( 10 * b ) ) ; return ; } if ( b == 1 && a == 9 ) { System . out . print ( 9 + " ▁ " + 10 ) ; return ; } System . out . print ( - 1 ) ; }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (type_identifier) name: (identifier) dimensions: (dimensions))) 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: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (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)))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (identifier))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (binary_expression left: (binary_expression left: (parenthesized_expression (binary_expression left: (decimal_integer_literal) right: (identifier))) right: (string_literal)) right: (parenthesized_expression (binary_expression left: (binary_expression left: (decimal_integer_literal) right: (identifier)) right: (decimal_integer_literal))))))) (return_statement))) (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (identifier) right: (decimal_integer_literal)) right: (identifier))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (binary_expression left: (binary_expression left: (parenthesized_expression (binary_expression left: (binary_expression left: (decimal_integer_literal) right: (identifier)) right: (decimal_integer_literal))) right: (string_literal)) right: (parenthesized_expression (binary_expression left: (decimal_integer_literal) right: (identifier))))))) (return_statement))) (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (identifier) right: (decimal_integer_literal)) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (binary_expression left: (binary_expression left: (decimal_integer_literal) right: (string_literal)) right: (decimal_integer_literal))))) (return_statement))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (unary_expression operand: (decimal_integer_literal)))))))