#include<stdio.h>
#include<math.h>
#include<algorithm>
#include<iostream>
using namespace std;
#define maxn 500020
int b[maxn],e[maxn],lson[maxn],rson[maxn],cnt[maxn],m[maxn],lbd[maxn],rbd[maxn],line[maxn];
int root,n,nn;
struct node
{
int x,y1,y2,index;
int left;
};
node seg[maxn];
int ymap[maxn],used[maxn];
void build(int l,int r)
{
n++;
int v=n;
b[v]=l;e[v]=r;
if(r-l>1)
{
lson[v]=n+1;
build(l,(l+r)/2);
rson[v]=n+1;
build((l+r)/2,r);
}
return ;
}
void updatem(int v)
{
if(cnt[v]>0)m[v]=ymap[e[v]]-ymap[b[v]];
else
{
if(e[v]-b[v]==1)m[v]=0;
else m[v]=m[lson[v]]+m[rson[v]];
}
// printf("%d %d %d\n",v,cnt[v],m[v]);
return ;
}
void updateline(int v)
{
if(cnt[v]>0)lbd[v]=rbd[v]=line[v]=1;
else
{
if(e[v]-b[v]==1)lbd[v]=rbd[v]=line[v]=0;
else
{
lbd[v]=lbd[lson[v]];
rbd[v]=rbd[rson[v]];
line[v]=line[lson[v]]+line[rson[v]]-rbd[lson[v]]*lbd[rson[v]];
}
}
// printf("%d %d %d %d lbd\n",v,lbd[v],rbd[v],line[v]);
return ;
}
void insert(int l,int r,int v)
{
if(!v)return ;
if(l<=ymap[b[v]]&&ymap[e[v]]<=r)
{
cnt[v]++;
lbd[v]=rbd[v]=1;
}
else if(e[v]-b[v]>1)
{
if(l<ymap[(b[v]+e[v])/2])insert(l,r,lson[v]);
if(r>ymap[(b[v]+e[v])/2])insert(l,r,rson[v]);
}
updatem(v);
updateline(v);
return ;
}
void del(int l,int r,int v)
{
if(!v)return ;
if(l<=ymap[b[v]]&&ymap[e[v]]<=r)
{
cnt[v]--;
if(l==ymap[b[v]])lbd[v]=0;
if(r==ymap[e[v]])rbd[v]=0;
}
else if(e[v]-b[v]>1)
{
if(l<ymap[(b[v]+e[v])/2])del(l,r,lson[v]);
if(r>ymap[(b[v]+e[v])/2])del(l,r,rson[v]);
}
updatem(v);
updateline(v);
return ;
}
bool cmp(node a,node b)
{
return (a.x<b.x)||(a.x==b.x&&a.y1<b.y1);
}
void solve()
{
root=1;n=0;
memset(lson,0,sizeof(lson));memset(rson,0,sizeof(rson));
memset(cnt,0,sizeof(cnt));memset(m,0,sizeof(m));
memset(line,0,sizeof(line));
memset(lbd,0,sizeof(lbd));memset(rbd,0,sizeof(rbd));
memset(used,0,sizeof(used));
sort(ymap,ymap+nn*2);
int tn=std::unique(ymap,ymap+nn*2)-ymap;
build(0,tn-1);
sort(seg,seg+nn*2,cmp);
int prem,prel,i;
__int64 ans=0;
// for(i=0;i<=n;i++)printf("%d %d %d %d\n",i,b[i],e[i],cnt[i]);
insert(seg[0].y1,seg[0].y2,1);
prem=m[1];prel=line[1];
// used[seg[0].index]=1;
// ans+=prem;
// printf("%d %d |",nn,ans);
// printf("%d ans %d %d line:::%d \n",ans,seg[0].y1,seg[0].y2,line[1]);
for(i=1;i<nn*2;i++)
{
if(seg[i].left)
{
insert(seg[i].y1,seg[i].y2,1);
}
else
{
// printf("delete ");
del(seg[i].y1,seg[i].y2,1);
}
ans+=(__int64)prem*(seg[i].x-seg[i-1].x);
// ans+=prel*(seg[i].x-seg[i-1].x)*2;
// printf("%d %d %d %d %d %d\n",i,seg[i].x,seg[i-1].x,ans,m[1],prem);
prem=m[1];prel=line[1];
}
printf("%I64d\n",ans);
return ;
}
int main()
{
// freopen("in.txt","r",stdin);
int i,x1,x2,y1,y2;
int a,b,c;
scanf("%d",&nn);
for(i=0;i<2*nn;i+=2)
{
scanf("%d%d%d",&a,&b,&c);
x1=a;x2=b;y1=0;y2=c;
ymap[i]=y1;ymap[i+1]=y2;
seg[i].index=i;
seg[i].x=x1;seg[i].y1=y1;seg[i].y2=y2;
seg[i].left=1;
seg[i+1].index=i;
seg[i+1].x=x2;seg[i+1].y1=y1;seg[i+1].y2=y2;
seg[i+1].left=0;
}
if(nn==0)
{
printf("0\n");return 0;
}
solve();
return 0;
}
