uint64_convert_hexString

#include <iostream>
#include <string>
using namespace std;

int main() {
    cout << "HexString:\n";
    char buffer [16];
    uint64_t i = 14923743766755009687U;
    snprintf(buffer, 16, "%016lx",i);
    string hexStr(buffer, 16);
    cout << hexStr;
    return 0;
}