def sum(n):
if type(n) != type([]) and type(n) != type(()):
return None
if len(n) == 0:
return None
sum = 0
for i in range(0,len(n)):
sum = sum+n[i]
return sum
n=(1,2,4)
sum(n)
求最大值
def max(n):
if type(n) != type([]) and type(n) != type(()):
return None
if len(n) == 0:
return None
for i in range(0,len(n)):
for j in range(i+1,len(n)):
a=n[i]
b=n[j]
if a<b:
n[i]=n[j]
n[j]=a
return n[0]
n=[1,2,3]
max(n)