static int highestPower ( String str , int len ) {
  int ans = 0 ;
  for ( int i = len - 1 ;
  i >= 0 ;
  i -- ) {
    if ( str . charAt ( i ) == '0' ) ans ++ ;
    else break ;
  }
  return ans ;
}

static int highestPower ( String str , int len ) { int ans = 0 ; for ( int i = len - 1 ; i >= 0 ; i -- ) { if ( str . charAt ( i ) == '0' ) ans ++ ; else break ; } return ans ; }
(method_declaration (modifiers) type: (integral_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (type_identifier) 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: (binary_expression left: (identifier) right: (decimal_integer_literal)))) condition: (binary_expression left: (identifier) right: (decimal_integer_literal)) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))) right: (character_literal))) consequence: (expression_statement (update_expression (identifier))) alternative: (break_statement)))) (return_statement (identifier))))