public static void main ( String [ ] args ) throws IOException {
  Scanner input = new Scanner ( System . in ) ;
  int x = input . nextInt ( ) ;
  int count = 0 ;
  for ( int i = 1 ;
  i <= x ;
  i ++ ) {
    for ( int j = 1 ;
    j <= i ;
    j ++ ) {
      count += 1 ;
      if ( count == x ) {
        System . out . println ( i ) ;
        System . exit ( 0 ) ;
      }
    }
  }
}

public static void main ( String [ ] args ) throws IOException { Scanner input = new Scanner ( System . in ) ; int x = input . nextInt ( ) ; int count = 0 ; for ( int i = 1 ; i <= x ; i ++ ) { for ( int j = 1 ; j <= i ; j ++ ) { count += 1 ; if ( count == x ) { System . out . println ( i ) ; System . exit ( 0 ) ; } } } }
(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: (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 (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 (assignment_expression left: (identifier) right: (decimal_integer_literal))) (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 (identifier)))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (decimal_integer_literal))))))))))))