static int getPairs ( int arr [ ] , int n ) {
  HashSet < Pair > h = new HashSet < Pair > ( ) ;
  for ( int i = 0 ;
  i < n - 1 ;
  i ++ ) {
    for ( int j = i + 1 ;
    j < n ;
    j ++ ) {
      Pair < Integer , Integer > p = new Pair < > ( arr [ i ] , arr [ j ] ) ;
      h . add ( p ) ;
    }
  }
  return h . size ( ) ;
}

static int getPairs ( int arr [ ] , int n ) { HashSet < Pair > h = new HashSet < Pair > ( ) ; for ( int i = 0 ; i < n - 1 ; i ++ ) { for ( int j = i + 1 ; j < n ; j ++ ) { Pair < Integer , Integer > p = new Pair < > ( arr [ i ] , arr [ j ] ) ; h . add ( p ) ; } } return h . size ( ) ; }
(method_declaration (modifiers) type: (integral_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (integral_type) name: (identifier) dimensions: (dimensions)) (formal_parameter type: (integral_type) name: (identifier))) body: (block (local_variable_declaration type: (generic_type (type_identifier) (type_arguments (type_identifier))) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (generic_type (type_identifier) (type_arguments (type_identifier))) arguments: (argument_list)))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (binary_expression left: (identifier) right: (decimal_integer_literal))) update: (update_expression (identifier)) body: (block (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (identifier) right: (decimal_integer_literal)))) condition: (binary_expression left: (identifier) right: (identifier)) update: (update_expression (identifier)) body: (block (local_variable_declaration type: (generic_type (type_identifier) (type_arguments (type_identifier) (type_identifier))) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (generic_type (type_identifier) (type_arguments)) arguments: (argument_list (array_access array: (identifier) index: (identifier)) (array_access array: (identifier) index: (identifier)))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))))))) (return_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))))