#include<iostream>

 #include<cstdio>

 #include<cstring>

 #include<algorithm>

 #include<cstdlib>

 using namespace std;

 const int MAXN=+;

 typedef long long ll;

 int n,d[MAXN],c[MAXN];

 ll psum[MAXN],pdsum[MAXN],f[MAXN],y[MAXN];

 int que[MAXN];

 double slop(int i,int j)

 {

     ll x1=psum[i];

     ll x2=psum[j];

     ll y1=f[i]+pdsum[i];

     ll y2=f[j]+pdsum[j];

     return(1.0*(y2-y1)/(x2-x1));

 }

 void init()

 {

     scanf("%d",&n);

     memset(psum,,sizeof(psum));

     memset(pdsum,,sizeof(pdsum));

     memset(f,,sizeof(f));

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

     {

         int p;

         scanf("%d%d%d",&d[i],&p,&c[i]);

         psum[i]=psum[i-]+(ll)p;

         pdsum[i]=pdsum[i-]+(ll)p*d[i];

     }

 }

 ll dp()

 {

     int head=,tail=;

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

     {

         while (head+<tail && slop(que[head],que[head+])<=1.0*d[i]) head++;

         int j=que[head];

         f[i]=d[i]*psum[i]-pdsum[i]+c[i]+f[j]-d[i]*psum[j]+pdsum[j];

         while (head+<tail && slop(que[tail-],i)<=slop(que[tail-],que[tail-])) tail--;

         que[tail++]=i;

     }

     return(f[n]);

 }

 int main()

 {

     init();

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

     return ;

 }