static long countPairsWithKDiff ( int arr [ ] , int n , int k ) {
  long ans = 0 ;
  for ( int i = 0 ;
  i < n - 1 ;
  ++ i ) {
    for ( int j = i + 1 ;
    j < n ;
    ++ j ) {
      int xoredNum = arr [ i ] ^ arr [ j ] ;
      if ( k == bitCount ( xoredNum ) ) ++ ans ;
    }
  }
  return ans ;
}

static long countPairsWithKDiff ( int arr [ ] , int n , int k ) { long ans = 0 ; for ( int i = 0 ; i < n - 1 ; ++ i ) { for ( int j = i + 1 ; j < n ; ++ j ) { int xoredNum = arr [ i ] ^ arr [ j ] ; if ( k == bitCount ( xoredNum ) ) ++ ans ; } } return ans ; }
(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)) (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: (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: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (array_access array: (identifier) index: (identifier))))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (method_invocation name: (identifier) arguments: (argument_list (identifier))))) consequence: (expression_statement (update_expression (identifier)))))))) (return_statement (identifier))))