#include<bits/stdc++.h>

 #define N 10000010

 #define inf 1000000000

 using namespace std;

 typedef long long ll;

 int tot=,sumv[N<<],ls[N],rs[N];

 int n,rt,cnt=;ll ans=;

 void change(int &o,int l,int r,int ql,int qr,int v){

     if(l>r)return;

     if(!o)o=++cnt;

     if(ql<=l&&r<=qr){sumv[o]=max(sumv[o],v);return;}

     int mid=(l+r)>>;

     if(ql<=mid)change(ls[o],l,mid,ql,qr,v);

     if(qr>mid)change(rs[o],mid+,r,ql,qr,v);

 }

 void dfs(int o,int l,int r,int maxv){

     if(!o)return;

     maxv=max(maxv,sumv[o]);

     if(!ls[o]&&!rs[o]){ans+=1LL*(r-l+)*maxv;return;}

     int mid=(l+r)>>;

     dfs(ls[o],l,mid,maxv);dfs(rs[o],mid+,r,maxv);

     if(!ls[o])ans+=1LL*(mid-l+)*maxv;

     if(!rs[o])ans+=1LL*(r-mid)*maxv;

 }

 inline int read(){

     int f=,x=;char ch;

     do{ch=getchar();if(ch=='-')f=-;}while(ch<''||ch>'');

     do{x=x*+ch-'';ch=getchar();}while(ch>=''&&ch<='');

     return f*x;

 }

 int main(){

     n=read();

     for(int i=;i<=n;i++){

         int l=read(),r=read(),k=read();

         change(rt,,inf,l,r-,k);

     }

     dfs(rt,,inf,);

     printf("%lld\n",ans);

     return ;

 }