快读

inline int read()

{  
   int s=0,w=1;  
   char ch=getchar();  
   while(ch<='0'||ch>'9'){if(ch=='-')w=-1;ch=getchar();}  
   while(ch>='0'&&ch<='9') s=s*10+ch-'0',ch=getchar();  
   return s*w;  
}  

int main()

{
    int n=read();
}