请教高手一个多线程编程的问题

#include<windows.h>
#include<iostream.h>

DWORD WINAPI Fun1Proc(LPVOID lpParameter);
DWORD WINAPI Fun2Proc(LPVOID lpParameter);
int i=0;
int ticket=100;
void main()
{
HANDLE hThread1;
HANDLE hThread2;
hThread1=CreateThread(NULL,0,Fun1Proc,NULL,0,NULL);
hThread2=CreateThread(NULL,0,Fun2Proc,NULL,0,NULL);
CloseHandle(hThread1);
CloseHandle(hThread2);
while(i++<10000)
{
cout<<"main is running"<<endl;
}
}

DWORD WINAPI Fun1Proc(LPVOID lpParameter)
{
    while(i++<10000)
    {
    while(1)
    {
    if(ticket>0)
        cout<<"thread1 sell ticket: "<<ticket--<<endl;
    else
        break;
    }}
    return 0;
}

DWORD WINAPI Fun2Proc(LPVOID lpParameter)
{
    while(1)
    {
if(ticket>0)
        cout<<"thread2 sell ticket: "<<ticket--<<endl;
else
break;
    }
return 0;
}这个程序中，不采用Sleep（）函数而采用while循环来使主函数不会那么早结束，但为什么主函数中改成//cout<<"main is running"<<endl;，注释起来，则线程1,2都不会执行了？
若不注释，将线程1中去掉任何一个循环，为什么也会导致线程1,2不能执行？