inline long long read(){ ll x=0;char c=getchar();bool f=false; while(!isdigit(c)){ f|=(c=='-); c=getchat(); } while(isdigit(c)){ x=(x<<1)+(x<<3)+c-48; c=getchar(); } return f?-x:x; } CSps用的读优,是不是要爆零了QAQ