public static void main ( String [ ] args ) throws IOException {
  Scanner sc = new Scanner ( System . in ) ;
  long n = sc . nextInt ( ) ;
  long a = sc . nextInt ( ) ;
  long b = sc . nextInt ( ) ;
  if ( a > b ) {
    System . out . println ( 0 ) ;
    return ;
  }
  if ( n == 1 ) {
    System . out . println ( a == b ? 1 : 0 ) ;
    return ;
  }
  else {
    System . out . println ( ( long ) ( ( b - a ) * ( n - 2 ) + 1 ) ) ;
  }
}

public static void main ( String [ ] args ) throws IOException { Scanner sc = new Scanner ( System . in ) ; long n = sc . nextInt ( ) ; long a = sc . nextInt ( ) ; long b = sc . nextInt ( ) ; if ( a > b ) { System . out . println ( 0 ) ; return ; } if ( n == 1 ) { System . out . println ( a == b ? 1 : 0 ) ; return ; } else { System . out . println ( ( long ) ( ( b - a ) * ( n - 2 ) + 1 ) ) ; } }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (array_type element: (type_identifier) dimensions: (dimensions)) name: (identifier))) (throws (type_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)))) (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 (decimal_integer_literal)))) (return_statement))) (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 (ternary_expression condition: (binary_expression left: (identifier) right: (identifier)) consequence: (decimal_integer_literal) alternative: (decimal_integer_literal))))) (return_statement)) alternative: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (cast_expression type: (integral_type) value: (parenthesized_expression (binary_expression left: (binary_expression left: (parenthesized_expression (binary_expression left: (identifier) right: (identifier))) right: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal)))) right: (decimal_integer_literal)))))))))))