def puzzle(L, i, visited):
    if L[i] == 0:
        return False
    if i in visited:
        return False
    visited.add(i)
    if i == len(L) - 1:
        return True
    if i + L[i] == len(L) - 1:
        return True
    if not ((i - L[i]) > 0) and not ((i + L[i]) < len(L) - 1):
        return False
    if ((i - L[i]) > 0) and ((i + L[i]) < len(L) - 1):
        return puzzle(L, i + L[i], visited) or puzzle(L, i - L[i], visited)
    if i + L[i] > len(L) - 1:
        return puzzle(L, i - L[i], visited)
    if i - L[i] <= 0:
        return puzzle(L, i + L[i], visited)