读取int的时候可以加速
inline int ReadInt()
{
char ch = getchar();
bool sign = 1;
if(ch == '-') sign = 0;
int data = 0;
while (ch < '0' || ch > '9') ch = getchar();
do{data = data*10 + ch-'0';ch = getchar();} while (ch >= '0' && ch <= '9');
return sign ? data : -data;
}