#include<bits/stdc++.h>
#define ll long long
using namespace std;
const int MAXN=5e5;
ll a[MAXN],b[MAXN],c[MAXN],s[MAXN<<1],ans=-8e18;
int n,m,v[MAXN<<1];
signed main() {
	scanf("%d",&n),v[++m]=1;
	for(int i=1;i<=n;++i) {
		scanf("%lld%lld%lld",&a[i],&b[i],&c[i]);
		v[++m]=a[i],v[++m]=b[i];
	}
	sort(v+1,v+m+1),m=unique(v+1,v+m+1)-v-1;
	for(int i=1;i<=n;++i) {
		s[lower_bound(v+1,v+m+1,a[i])-v]+=2*c[i];
		s[lower_bound(v+1,v+m+1,b[i])-v]+=2*c[i];
		s[1]-=2*c[i];
	}
	for(int i=2;i<=m;++i) s[i]+=s[i-1];
	for(int i=1;i<=m;++i) for(int j=i;j<=m;++j) ans=max(ans,s[i]+s[j]-4ll*v[i]*v[j]);
	printf("%lld\n",ans);
	return 0;
}