#include <iostream>
using namespace std;
int i, n, v[1000000], maxim, m1[1000000], m2[1000000], a[1000000], b[1000000], c[1000000];
int main()
{
    cin>>n;
    for(i=1; i<=n; i++) cin>>a[i]>>b[i]>>c[i];
    m1[1]=0;
    m2[1]=a[1];
    v[1]=0;
    for(i=2; i<=n; i++)
    {
        m1[i]=max(m1[i-1], m2[i-1]);
        m2[i]=m1[i-1]+a[i];
        if(v[i-1]==0)  m2[i-1]=m2[i-1]-a[i-1]+b[i-1];
        else m2[i-1]=m2[i-1]-b[i-1]+c[i-1];
        v[i-1]++;
        if(m2[i-1]+b[i]>m2[i]) m2[i]=m2[i-1]+b[i], v[i]++;
    }
    maxim=max(m1[n], m2[n]);
    cout<<maxim<<'\n';
    return 0;
}