CMakeLists.txt

cmake_minimum_required(VERSION 2.8.10)
project("string-switch")
set(CMAKE_CXX_FLAGS "-std=c++11 ${CMAKE_CXX_FLAGS}")
add_executable("string-switch" "string-switch.cxx")

string-switch.cxx

#include <iostream>
#include <cstdint>
#include <stdexcept>

constexpr uint_fast64_t to_int(const char* const s, const size_t h = 0)
{ return !s[h] ? 5381ull : (to_int(s, h + 1) * 33) ^ s[h] ; }

int main(const int n, const char* const * const as)
try
{
  if(n < 2)
    throw std::runtime_error("require argument");

  switch(to_int(as[1]))
  {
#define CASE(x) \
  case to_int(x): std::cout << x ": " << to_int(x) << "\n"; break;
  CASE("abc")
  CASE("def")
  CASE("xyz")
  CASE("this is a pen")
  CASE("昆布茶")
  CASE("ほんだし")
#undef CASE
  default:
    throw std::runtime_error("unkown case");
  }
}
catch(const std::exception& e)
{
  std::cerr << "exception: " << e.what() << "\n";
  return 1;
}

results:

./string-switch abc
abc: 193415941

./string-switch def
def: 193410914

./string-switch "this is a pen"
this is a pen: 1200543880250723683

./string-switch "昆布茶"
昆布茶: 18196897787883024465

./string-switch "ほんだし"
ほんだし: 12022550795961921433