还有for(;;)不懂

exit(0)结束程序
for(;;)就是无条件循环，直到碰到break语句退出循环 或者 死机

那可以用标准c中的什么代替呢 另外Presentation Error (PE):是什么错误啊
Your program's output format is not exactly the same as required by the problem, although the output is correct. This usually means the existence of omitted or extra blank characters (white spaces, tab characters and/or new line characters) between any two non-blank characters, and/or blank lines (a line consisting of only blank characters) between any two non-blank lines. Trailing blank characters at the end of each line and trailing blank lines at the of output are not considered format errors. Check the output for spaces, blank lines, etc. against the problem's output specification.

你们程序的输出格式不完全一样，所需要的问题虽然产量是正确的。这通常意味着存在遗漏或额外的空白字符（白位，统计表字符和/或新线字符）之间的任何两个非空白字符，和/或空白线（一条线，其中只有空白字符）之间的任何两个非-空白线。尾空白字符在每年年底的路线和尾空行上的输出并不被视为格式错误。检查的输出位，空行等，对这个问题的输出规格

大体应该就是这个意思。。。。