#include <fstream>
using namespace std;
ifstream f("stdin");
ofstream g("stdout");
int i, n, v[1000000], maxim, m1[1000000], m2[1000000], a[1000000], b[1000000], c[1000000];
int maxi(int x, int y)
{
    if(x>y) return x;
    return y;
}
int main()
{
    f>>n;
    for(i=1; i<=n; i++) f>>a[i]>>b[i]>>c[i];
    m1[1]=0;
    m2[1]=a[1];
    v[1]=0;
    for(i=2; i<=n; i++)
    {
        m1[i]=maxi(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=maxi(m1[n], m2[n]);
    g<<maxim<<'\n';
    return 0;
}