快读板子fread

 struct ios {
     inline char read(){
         static const int IN_LEN=<<|;
         static char buf[IN_LEN],*s,*t;
         return (s==t)&&(t=(s=buf)+fread(buf,,IN_LEN,stdin)),s==t?-:*s++;
     }

     template <typename _Tp> inline ios & operator >> (_Tp&x){
         static char c11,boo;
         for(c11=read(),boo=;!isdigit(c11);c11=read()){
             if(c11==-)return *this;
             boo|=c11=='-';
         }
         for(x=;isdigit(c11);c11=read())x=x*+(c11^'');
         boo&&(x=-x);
         return *this;
     }
 } io;

 int main(){io>>a>>b;}