for_each_example.cpp

#include <algorithm>
#include <cstdint>
#include <iomanip>
#include <iostream>
#include <numeric>
#include <string>
#include <vector>

struct HashString {
  void operator()(const std::string &s) {
    hash = std::accumulate(s.begin(), s.end(), hash, hash_char);
  }
  uint32_t hash = 0;
};

template <typename Cont>
uint32_t hash_all_strings(const Cont& v) {
    const auto hasher = std::for_each(v.begin(), v.end(), HashString());
    return hasher.hash;
}

int main() {
    std::vector<std::string> v{"one", "two", "three", "four", "five" };
    uint32_t hash = hash_all_strings(v);
    std::cout << "Hash: " << hash << std::dec << std::endl;
}