#include <cstdio>
#include <cstdlib>
#include <vector>
#include <string>
#define NOMINMAX
#include <windows.h>
#include <iostream>

const int count = 250*1000;
const int max_length = 250;

std::vector<std::string> strings1 = std::vector<std::string>(count);
std::vector<std::string> strings2 = std::vector<std::string>(count);
std::string allowed_chars = std::string("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ");

double elapsed_ms(LARGE_INTEGER start, LARGE_INTEGER end) {
    LARGE_INTEGER frequency;
    QueryPerformanceFrequency(&frequency);
    return (end.QuadPart - start.QuadPart) * 1000 / (double) frequency.QuadPart;
}

int test(char* a, char* b) {
    return *a != *b;
}

void compare_cstrings(int count, int length) {
    std::vector<char*> shortstrings1 = std::vector<char*>(count);
    std::vector<char*> shortstrings2 = std::vector<char*>(count);

    LARGE_INTEGER start, end;

    for (int str_id = 0; str_id < count; str_id++) {
        shortstrings1[str_id] = new char[length + 1];
        shortstrings2[str_id] = new char[length + 1];
        strings1[str_id].copy(shortstrings1[str_id], length, 0);
        strings2[str_id].copy(shortstrings2[str_id], length, 0);
        shortstrings1[str_id][length] = shortstrings2[str_id][length] = '\0';
    }

    int matches = 0;

    QueryPerformanceCounter(&start);
    for (int str_id = 0; str_id < count; str_id++)
        if (test(shortstrings1[str_id], shortstrings2[str_id]) == 0)
            matches++;
    QueryPerformanceCounter(&end);

    for (int str_id = 0; str_id < count; str_id++) {
        delete[] shortstrings1[str_id];
        delete[] shortstrings2[str_id];
    }

    printf("C-Strings\t%d\t%d\t%f\tms\t(%d matches)\n", count, length, elapsed_ms(start, end), matches);
}

int main(int argc, char** argv) {
    srand(0);

    for (int str_id = 0; str_id < count; str_id++) {
        std::string str1 = std::string(max_length, ' ');
        std::string str2 = std::string(max_length, ' ');

        for (int char_id = 0; char_id < max_length; char_id++) {
            str1[char_id] = allowed_chars[std::rand() % allowed_chars.length()];
            str2[char_id] = allowed_chars[std::rand() % allowed_chars.length()];
        }

        strings1[str_id] = str1;
        strings2[str_id] = str2;
    }

    for (int length = 1; length <= 250; length++)
        compare_cstrings(count, length);
}