循环
for 循环
range左闭右开
省略最后一个参数
def sum(n):
total=0
for x in range(n+1):
tltal+=x
return total#range默认起始为0
添加第三个参数(步长
def sum(m,n,k)
for i in range(1,10,2)
print(i)
0 2 4 6 8
只对m到n奇数求和
def sum(m,n):
total =0
for x in range(m,n+1):
if x%2==1:
total+=x
return total
sum(4,10)===(5+7+9)
for i in range(10,0,-1)
print(i)
10 9 8 7 6 5 4 3 2 1
def pmy(n):
for i in range(n):
print(i,end=" ")
for x in range(x):
print("*",end=" ")
print()
pmy(5)
0
1 *
2 * *
3 * * *
4* * * *
while循环
不知道循环什么时候停
def id(n):
n=abs(n)
while n>=10:
n=n//10
return n
id(-79)
7
依次找出n个4或7的整数倍
def isM(x):
return((x%4)==0)or((x%7)==0)
def nthM(n):
found=0
guess=-1
while found<=n:
guess+=1
isM(guess):
found+=1
return n
print("倍数",end="")
for n in range(15):#找15个
print(nthM(n),end="")
break与continue
for i in range(200):
if n%3==0:
continue#跳过这个循环
elif n==8:
break#跳出当前整个循环
else:
pass#啥也不做
print(n,end="")
1 2 4 5 7
假-死循环
练习
判断质数
慢
isPrime(n):
if n<2:
return False
for i in range(2,n):
if n%i==0:
retuen False
return True
快
def isprime(n):
if n<2:
return False
if n==2:
return True
if n%2==0:
return False
max=round(n**0.5)
for f in range(3,max+1,2):
if n%f==0:
return False
return True
标签:10,range,循环,print,total,def
From: https://www.cnblogs.com/aijingyn/p/17872477.html