public static void main ( String [ ] args ) {
  Scanner sc = new Scanner ( System . in ) ;
  int a = sc . nextInt ( ) ;
  int b = sc . nextInt ( ) ;
  int c = sc . nextInt ( ) ;
  int n = sc . nextInt ( ) ;
  if ( a < c || b < c ) {
    System . out . println ( "-1" ) ;
  }
  else {
    int students = ( a - c ) + ( b - c ) + c ;
    int failed_students = n - students ;
    if ( failed_students <= 0 ) {
      System . out . println ( "-1" ) ;
    }
    else {
      System . out . println ( failed_students ) ;
    }
  }
}

public static void main ( String [ ] args ) { Scanner sc = new Scanner ( System . in ) ; int a = sc . nextInt ( ) ; int b = sc . nextInt ( ) ; int c = sc . nextInt ( ) ; int n = sc . nextInt ( ) ; if ( a < c || b < c ) { System . out . println ( " - 1" ) ; } else { int students = ( a - c ) + ( b - c ) + c ; int failed_students = n - students ; if ( failed_students <= 0 ) { System . out . println ( " - 1" ) ; } else { System . out . println ( failed_students ) ; } } }
(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: (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)))) (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: (binary_expression left: (identifier) right: (identifier)) right: (binary_expression left: (identifier) right: (identifier)))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal))))) alternative: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (binary_expression left: (parenthesized_expression (binary_expression left: (identifier) right: (identifier))) right: (parenthesized_expression (binary_expression left: (identifier) right: (identifier)))) right: (identifier)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (identifier) right: (identifier)))) (if_statement condition: (parenthesized_expression (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 (string_literal))))) alternative: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))))))))