1 int read(){
2 char ch=getchar();int x=0,f=1;
3 while(ch<'0' || ch>'9') {if(ch=='-')f=-1;ch=getchar();}
4 while(ch>='0' && ch<='9'){x=x*10+ch-'0';ch=getchar();}
5 return x*f;
6 }
int read(){
char ch=getchar();int x=0,f=1; while(ch<'0' || ch>'9') {if(ch=='-')f=-1;ch=getchar();} while(ch>='0' && ch<='9'){x=x*10+ch-'0';ch=getchar();} return x*f; }