#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <cstdio>
#include <cstdint>
#include <cmath>
 
class hr_timer {
    double  m_resolution;
 
public:
    hr_timer() {
        uint64_t frequency;
        QueryPerformanceFrequency( (LARGE_INTEGER *)&frequency );
        m_resolution = 1e6 / float(frequency);
    }
 
    void wait( uint64_t us /* microseconds */ ) {
        if ( us ) {

#include <winsock2.h>
#include <ws2tcpip.h>
#include <windows.h>
#include <mstcpip.h>
 
#include <cstdio>
#include <cstdint>
#include <cctype>
#include <string>
#include <map>
 
///
/// [url]https://en.wikipedia.org/wiki/IPv4[/url]
///
struct ip_header {
    uint8_t     ver_ihl;
    uint8_t     dscp_ecn;
    uint16_t    len;