windows timestamp (C++)

我创建了windows时间戳（）函数，但我通过PHP microtime（）函数检查了错误的数字：

• C++=1409802313
• PHP=11410655505

在这个闲置的C++编写的代码中：

#include <windows.h>
#include <iostream> // <--- Console I/O
#include <cstdlib> // <--- Command Line
#include <sstream>
using namespace std;
void print(string value){cout << value;}
string parseStr(int value)
{
ostringstream stream;
stream<<value<<flush;
return stream.str();
}

// ============================================================
//                         TIMESTAMP
// ============================================================
string timestamp()
{
SYSTEMTIME system_time;
GetLocalTime(&system_time);
int year = system_time.wYear;
int month = system_time.wMonth;
int day = system_time.wDay;
int hour = system_time.wHour;
int minute = system_time.wMinute;
int second = system_time.wSecond;
int milliseconds = system_time.wMilliseconds;
int day_of_year = 0;
 if (month > 1){day_of_year += 31;} // Sausis
 if (month > 2){day_of_year += 28;} // Vasaris
 if (month > 3){day_of_year += 31;} // Kovas
 if (month > 4){day_of_year += 30;} // Balandis
 if (month > 5){day_of_year += 31;} // Geguze
 if (month > 6){day_of_year += 30;} // Birzelis
 if (month > 7){day_of_year += 31;} // Liepa
 if (month > 8){day_of_year += 31;} // Rugpjutis
 if (month > 9){day_of_year += 30;} // Rugsejis
 if (month > 10){day_of_year += 31;} // Spalis
 if (month > 11){day_of_year += 30;} // Lapkritis
 if (month > 12){day_of_year += 31;} // Gruodis
day_of_year += day;
int time = 0;
time += (year - 1970) * 31536000;
time += day_of_year * 86400;
time += hour * 3600;
time += minute * 60;
time += second;
string time_string;
time_string = parseStr(time);
return time_string;
}
// ============================================================
int main()
{
 while(true)
 {
 system("cls");
 string time = timestamp();
 print(time);
 Sleep(100);
 }
return 0;
}

我是计算错误还是整数类型错误？：（