Hashing a string to an integer in c++ -


i trying figure out conversion process strings ints. doing program hashing, in key value hashed name of state. research, seems atoi() not work.

do need break each letter of word down , individually convert? use ascii? going in wrong direction?

i lost, information fantastic. thanks!

c++11 introduces implementation defined hashing function called std::hash in header <functional> has speciality string classes std::string, std::wstring, etc.

it's simple doing this:

#include <iostream> #include <functional> //for std::hash #include <string>  int main() {     std::string str = "hello world";     std::hash<std::string> hasher;     auto hashed = hasher(str); //returns std::size_t     std::cout << hashed << '\n'; //outputs 2146989006636459346 on machine }

specializing std::hash user defined types isn't complex either. note there no std::hash specialization const char* or of c-strings.


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