如何使用SHA1散列算法在c++中散列系统时间？

#include <iostream>
#include <iomanip>
#include <openssl/sha.h>
#include <ctime>

std::string getSystemTime() {
    std::time_t now = std::time(nullptr);
    return std::ctime(&now);
}

std::string sha1Hash(const std::string& input) {
    unsigned char hash[SHA_DIGEST_LENGTH];
    SHA1(reinterpret_cast<const unsigned char*>(input.c_str()), input.length(), hash);

    std::stringstream ss;
    for (int i = 0; i < SHA_DIGEST_LENGTH; ++i) {
        ss << std::hex << std::setw(2) << std::setfill('0') << static_cast<int>(hash[i]);
    }

    return ss.str();
}

int main() {
    std::string systemTime = getSystemTime();
    std::string hashedTime = sha1Hash(systemTime);

    std::cout << "System Time: " << systemTime;
    std::cout << "SHA1 Hashed Time: " << hashedTime << std::endl;

    return 0;
}