[AtCoder][DP][Educational DP Contest]C-Vacation

#atcoder template
def main():
    import sys
    input = sys.stdin.readline
    #文字列入力の時は上記はerrorとなる。
    #ここにコード
    #input
    #another version
    #input
    n = int(input())
    a, b, c = [0] * n, [0] * n, [0] * n

    #output
    a[0], b[0], c[0] = map(int, input().split())

    for i in range(1, n):
        p, q, r = map(int, input().split())
        a[i] = p + max(b[i-1], c[i-1])
        b[i] = q + max(c[i-1], a[i-1])
        c[i] = r + max(a[i-1], b[i-1])

    print(max(a[-1], b[-1], c[-1]))

    #N = 1のときなどcorner caseを確認！
if __name__ == "__main__":
    main()

#atcoder template
def main():
    import sys
    input = sys.stdin.readline
    #文字列入力の時は上記はerrorとなる。
    #ここにコード
    #input
    n = int(input())
    a, b, c = [0] * (n+1), [0] * (n+1), [0] * (n+1)

    #output
    for i in range(n):
        p, q, r = map(int, input().split())
        a[i+1] = p + max(b[i], c[i])
        b[i+1] = q + max(c[i], a[i])
        c[i+1] = r + max(a[i], b[i])

    print(max(a[-1], b[-1], c[-1]))
    
    #N = 1のときなどcorner caseを確認！
if __name__ == "__main__":
    main()