又一次被fread坑了..

il char getc()
{
	static char buf[100000],*p1=buf,*p2=buf;
	return p1==p2&&(p2=(p1=buf)+fread(buf,1,100000,stdin),p1==p2)?EOF:*p1++;
}
il void scan(int &x)
{
	x=0;re int w=0;re char ch=0;
	while (!isdigit(ch)) w|=ch=='-',ch=getc();
	while (isdigit(ch)) x=(x<<1)+(x<<3)+(ch^48),ch=getc();
	if (w) x=-x;
}