看了大佬题解,学到了
Code
#include <bits/stdc++.h> using namespace std; int m,k,x; char s[10]; struct cmp{ bool operator () (const int & x,const int & y) const { if(abs(x-y)<=k) return false; return x < y; } }; set<int,cmp> se; int main(){ scanf("%d %d",&m,&k); while(m--){ scanf("%s",s);scanf("%d",&x); if(s[0]=='a') se.insert(x); else if(s[0]=='d') se.erase(x); else{ if (se.find(x)!=se.end()) puts("Yes"); else puts("No"); } } return 0; }