循环头 等待尾语句，若不符合条件则发回循环直到符合就往后运行

QueryPerformanceCounter(lgTick2) // 获得系统频率记数器的震荡次数

-Loop waiting for the end of the first statement, then do not meet the conditions found on the back loop until the next run QueryPerformanceCounter (lgTick2) // get the number of system oscillation frequency counter