inline int read()
{
int s=0,f=1;
char ch=getchar();
while(ch<'0'||ch>'9'){
if(ch=='-')
f=-1;
ch=getchar();
}
while(ch>='0'&&ch<='9'){
s=s*10+ch-'0';
ch=getchar();
}
return s*f;
}
inline void write(int x)
{
if(x<0){
putchar('-');
x=-x;
}
if(x>9)
write(x/10);
putchar(x%10+'0');
}