print a + b

print sorted(L)  # 返回新的list

print a[::-1]   # 切片的知識點

print ",".join([str(x) for x in a])   # 列表解析式和join方法，參數是str instance

print a[::2]

def prime(n):

    if n == 2:

        return True

    for i in range(2, n):

        if n % i ==0:

            return False

    return True

print [x for x in range(2, 100) if prime(x)]

L = sorted(L)
length = len(L)/2.0
if len(L) % 2 ==0:
    print (L[int(length-1]+L[int(length)])/2.0
else:
    print L[int(length)]

print a*b, (a+b)*2

def lcm(a, b):
    if a >b:
        greater = a
    else:
        greater = b
    while True:
        if greater % a ==0 and greater % b ==0:
            lcm = greater
            break
        greater +=1
    return lcm

print [x for x in range(1,min(a,b)) if a % x ==0 and b % x ==0][-1]

sum_i = 1
count = 0
for i in L：
    sum_i *= i
s = str(sum)[::-1]
for i in s:
    if i == '0':
        count +=1
    else:
        break
print count

sum_i = 1
count = 0
for i in L：
    sum_i *= i
s = str(sum)[::-1]
for i in s:
    if i !='0' and int(i) % 2 ==0:
        print 0
    elif i !='0' and int(i) % 2 !=0:
        print 1