Write a JavaScript program to display the city name if the string begins with "Los" or "New" otherwise return blank

function city_name(str) {
  if (str.length >= 3 && ((str.substring(0, 3) == 'Los')
                          || (str.substring(0, 3) == 'New')))
   
      {
          return str;
    }

  return '';
}

console.log(city_name("New York"));
console.log(city_name("Los Angeles"));
console.log(city_name("London"));