def max_iter(L):
    cmax = L[0]
    for i in L[1:]:
        if i > cmax:
            cmax = i
    return cmax

def max_recur(L):
    # base case
    if len(L) == 1:
        return L[0]

    # general case
    head = L[0]
    max_rest = max_recur(L[1:])
    if head > max_rest:
        return head
    else:
        return max_rest

def sum_iter(L):
    total = 0
    for i in L:
        total += i
    return total

def sum_recur(L):
    if len(L) == 1:
        return L[0]
    return L[0] + sum_recur(L[1:])