public static void main ( String [ ] args ) {
  ArrayList < Long > mo = new ArrayList < Long > ( ) ;
  long answer = 0 ;
  Scanner sc = new Scanner ( System . in ) ;
  int num = sc . nextInt ( ) ;
  int du = sc . nextInt ( ) ;
  String d = Integer . toBinaryString ( du ) ;
  for ( int i = 0 ;
  i != d . length ( ) ;
  i ++ ) {
    int c = sc . nextInt ( ) ;
    if ( d . charAt ( d . length ( ) - 1 - i ) == '1' ) {
      answer += c ;
    }
  }
  System . out . println ( + answer ) ;
}

public static void main ( String [ ] args ) { ArrayList < Long > mo = new ArrayList < Long > ( ) ; long answer = 0 ; Scanner sc = new Scanner ( System . in ) ; int num = sc . nextInt ( ) ; int du = sc . nextInt ( ) ; String d = Integer . toBinaryString ( du ) ; for ( int i = 0 ; i != d . length ( ) ; i ++ ) { int c = sc . nextInt ( ) ; if ( d . charAt ( d . length ( ) - 1 - i ) == '1' ) { answer += c ; } } System . out . println ( + answer ) ; }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (array_type element: (type_identifier) dimensions: (dimensions)) 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)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) (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: (type_identifier) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) update: (update_expression (identifier)) body: (block (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: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal)) right: (identifier)))) right: (character_literal))) consequence: (block (expression_statement (assignment_expression left: (identifier) right: (identifier))))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (unary_expression operand: (identifier)))))))