快读

template<typename Tp> inline void read(Tp&x)
{
    x=0;register bool f=1;
    register char c=getchar();
    for(;c<'0'||c>'9';c=getchar()) if(c=='-') f=0;
    for(;'0'<=c&&c<='9';c=getchar()) x=(x<<1)+(x<<3)+(c^48);
}