import core.bitop;
import std.algorithm;
import std.ascii;
import std.bigint;
import std.conv;
import std.functional;
import std.math;
import std.numeric;
import std.range;
import std.stdio;
import std.string;
import std.random;
import std.typecons;
import std.container;

alias sread = () => readln.chomp();
ulong MOD = 1_000_000_007;
ulong INF = 1_000_000_000_000;
alias Activity = Tuple!(long, "sea", long, "mount", long, "home");

T lread(T = long)()
{
    return readln.chomp.to!T();
}

T[] aryread(T = long)()
{
    return readln.split.to!(T[])();
}

void scan(TList...)(ref TList Args)
{
    auto line = readln.split();
    foreach (i, T; TList)
    {
        T val = line[i].to!(T);
        Args[i] = val;
    }
}

auto dp = new long[][](100_100, 3);
void main()
{
    auto n = lread();
    auto act = new long[][](n, 3);
    foreach (i; iota(n))
    {
        long a, b, c;
        scan(a, b, c);
        act[i] = [a, b, c];
    }
    foreach(i; iota(n))
    {
        foreach(j; iota(act[i].length))
        {
            dp[i + 1][j] = act[i][j] + max(dp[i][(j + 1) % 3], dp[i][(j + 2) % 3]);
        }
    }
    dp[n].reduce!(max).writeln();
}

auto max_rm(T)(T[] a, T recent = -1)
{
    long maxnum = -INF;
    foreach (i; iota(a.length))
        if (i != recent)
            maxnum = max(a[i], maxnum);

    return maxnum;
}
