rt

code:

#include<bits/stdc++.h>
// #pragma GCC optimize(1,2,3,"Ofast","inline")
#define endl "\n"
using namespace std;
inline int read(){
	int x=0,f=1;char ch=getchar();
	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;
}
inline void print(int x){
	if(x<0) putchar('-'),x=-x;
	if(x>9) print(x/10);
	putchar(x%10+'0');
}
// #define int long long
int n;
struct node{int d,h,bh;bool flag;}p[80005];
struct node1{
	int bh,h;
	bool operator<(const node1& b)const{
		return h<b.h;
	}
};
priority_queue<node1>q;
bool cmp(node a,node b){
	if(a.d==b.d) return a.flag>b.flag;
	return a.d<b.d;
}
bool fl[40005];
void solve(){
	n=read();
	for(int i=1;i<=n;i++){
		int a=read(),b=read(),c=read();
		p[i*2-1]={a,c,i,0};
		p[i*2]={b,c,i,1};
	}
	sort(p+1,p+n*2+1,cmp);
	int now=p[1].d,sum=0;
	q.push({p[1].bh,p[1].h});
	// cout<<p[1].flag<<" "<<sum<<" "<<p[1].d<<" "<<p[1].h<<" "<<p[1].bh<<" "<<now<<"\n";
	for(int i=2;i<=n*2;i++){
		node x=p[i];
		if(!x.flag){
			sum+=q.top().h*(p[i].d-now);
			now=p[i].d;
			q.push({p[i].bh,p[i].h});
		}else{
			sum+=q.top().h*(p[i].d-now);
			now=p[i].d;
			fl[p[i].bh]=1;
			while(!q.empty()&&q.top().bh==p[i].bh) q.pop();
		}
		// cout<<x.flag<<" "<<sum<<" "<<x.d<<" "<<x.h<<" "<<x.bh<<" "<<now<<"\n";
	}
	cout<<sum;
}
signed main(){
	int T=1;
	// T=read();
	while(T--) solve();
	return 0;
}