string
the key for hash_map operator()
in a class or struct:
class HashString { public: unsigned operator()(std::string const &str) const { return __gnu_cxx::hash<char const*>()(str.c_str()); } };then declare the hash_map like so:
hash_map<string,string,HashString> _blahBlahMemberVariable ;If you are using hashmap as an extension:
#include <ext/hash_map>the following technique for defining __gnu_cxx is useful:
#define __gnu_cxx std #include <ext/hash_map> using namespace std;link