problems

import itertools, random

de = [1, 5, 7, 2, 8]

def sum1(l): # for
    k = 0
    for i in l:
        k += i
    return k

def sum2(l): #while
    final = 0
    incr = 0
    while incr < len(l):
        final += l[incr]
        incr += 1
    return final

def sum3(l): #recursion
   if len(l) == 1:
        return l[0]
   else:
        return l[0] + sum3(l[1:])

def altern(l1, l2):
    return list(itertools.chain.from_iterable(zip(l1, l2)))

def fib():
    a = []
    for i_ in [0, 1, 1]: a.append(i_)
    for _ in range(3, 100):
        a.append(sum(a[-2:]))
    return a


def arrLarg(l):
    iterations = len(l)**4
    b = []
    for i in range(iterations):
        k = l[:]
        random.shuffle(k)
        k = int(''.join([str(i) for i in k]))
        b.append(k)
    b = list(set(b))
    b.sort(reverse=True)
    return b[0]