测试code:

#include<bits/stdc++.h>
#define int long long
using namespace std;
struct node{
	int dis,l,r,q_s;
	bool operator<(const node &T)const{return (T.q_s-T.dis)>(q_s-dis);}
};
multiset<node,less<node>>p;
signed main()
{
	p.insert({20,1,3,4});
	p.insert({15,2,4,9});
	p.insert({7,3,5,1});
	p.insert({0,0,2,2147483647});
	p.insert({0,4,6,2147483647});
	cout<<p.size()<<'\n';
	p.erase({7,3,5,1});//多删了{15,2,4,9}
	// p.erase(p.find({7,3,5,1}));//删成{15,2,4,9}了
	cout<<p.size()<<'\n';
	for(auto i:p)
	{
		cout<<i.dis<<" "<<i.l<<" "<<i.r<<" "<<i.q_s<<'\n';
	}
}

不解，玄关，谢谢