#include <cmath>
#include <chrono>
#include <iostream>

const int64_t MAX = 10000000;

int64_t while_count(int64_t n) {
    int64_t count = 0;
    while (n != 0) {
        n /= 10;
        count++;
    }
    return count;
}

int64_t log10_count(int64_t n) {
    return (int64_t) (log10(n) + 1);
}

int64_t string_count(int64_t n) {
    return std::to_string(n).size();
}

template<typename Function>
long time(Function func) {
    auto start = std::chrono::high_resolution_clock::now();
    for (int64_t i = 0; i < MAX; i++) {
        func(i);
    }
    auto finish = std::chrono::high_resolution_clock::now();
    auto duration = std::chrono::duration_cast<std::chrono::nanoseconds>(finish - start).count();
    std::cout << "Average " << duration / MAX << "ns" << std::endl;
    std::cout << "Total   " << duration << "ns" << std::endl;
    return duration;
}

void print_stats(const std::string &type, long time, long while_time) {
    auto diff = while_time - time;
    auto perc = static_cast<float>((float) diff / (float) while_time) * 100;

    std::cout << std::endl << type << " is " << diff / MAX << "ns faster per operation than while" << std::endl;
    std::cout << type << " is " << perc << "% faster than while-loop" << std::endl;
}

int main() {
    std::cout << "While-loop" << std::endl;
    auto while_time = time(while_count);

    std::cout << std::endl << "log10" << std::endl;
    auto log_time = time(log10_count);

    std::cout << std::endl << "string" << std::endl;
    auto string_time = time(string_count);

    print_stats("log", log_time, while_time);
    print_stats("string", string_time, while_time);

    return 0;
}