还是想不通，在对于64位数据，FAQ是这么说的Additional notes for GCC/G++:

For 64-bit integers, both long long int and __int64 is supported and they are equivalent. But only "%I64d" is supported when reading with scanf or writing with printf. "%lld" is not supported 

我是写的__int64和%I64d啊，会不会是pow的问题啊，总觉得这个函数不让人放心。大牛在处理乘方时用pow吗？需要用这么强制转换吗？