public static void check ( int n ) {
  int t = 0 ;
  for ( int i = 1 ;
  i <= n ;
  i ++ ) {
    t += i ;
    if ( t == n ) {
      System . out . println ( "YES" ) ;
      return ;
    }
  }
  System . out . println ( "NO" ) ;
}

public static void check ( int n ) { int t = 0 ; for ( int i = 1 ; i <= n ; i ++ ) { t += i ; if ( t == n ) { System . out . println ( " YES " ) ; return ; } } System . out . println ( " NO " ) ; }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (integral_type) name: (identifier))) body: (block (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 (expression_statement (assignment_expression left: (identifier) right: (identifier))) (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 (string_literal)))) (return_statement))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal))))))