快读
inline int read() { int X=0; bool flag=1; char ch=getchar(); while(ch<'0'||ch>'9') {if(ch=='-') flag=0; ch=getchar();} while(ch>='0'&&ch<='9') {X=(X<<1)+(X<<3)+ch-'0'; ch=getchar();} if(flag) return X; return ~(X-1); }
快输
inline void write(int X) { if(X<0) {X=~(X-1); putchar('-');} if(X>9) write(X/10); putchar(X%10+'0'); }