copy construction

#include <iostream>
#include <unordered_map>
#include <chrono>
using namespace std;

static const int kA = 54059;  // a prime
static const int kB = 76963;  // another prime
static const int kFinish = 37;  // also prime
uint32_t StrHash(const char* s, int size) {
  uint32_t h = kFinish;
  while (size > 0) {
    h = (h * kA) ^ (s[0] * kB);
    s++;
    size--;
  }
  return h;
}

const int UseridLen = 128;

class UserIdWrapper { // 比字符串作为key省不少空间
public:
  char s[UseridLen];
  UserIdWrapper(const char *t) {
		cout << "UserIdWrapper construction" << endl;
    for (int i = 0; i < UseridLen; i++) s[i] = t[i];
  }

  UserIdWrapper(const UserIdWrapper &rhs) {
		cout << "UserIdWrapper copy construction" << endl;
  }
	
  bool operator== (const UserIdWrapper &other) const {
    for (int i = 0; i < UseridLen; i++) {
      if (s[i] != other.s[i]) {
        return false;
      }
    }
    return true;
  }
};

namespace std {
    template <>
    struct hash<UserIdWrapper> {
        size_t operator()(const UserIdWrapper &k) const{
          return StrHash(k.s, UseridLen);
        }
    };
}

int main() {
	std::unordered_map<UserIdWrapper, int64_t> idx_user_id_list_;
	char s[UseridLen] = "12345;";
	int n = 0;
	auto start = std::chrono::system_clock::now();
	for (int i = 0; i < 1; i++) {
		idx_user_id_list_.emplace(std::make_pair(UserIdWrapper(s), 0));
	}
	auto end = std::chrono::system_clock::now();
	std::chrono::duration<double> elapsed_seconds = end-start;
	cout << "elapsed time: " << elapsed_seconds.count() << "s" << endl;
}