break:是用于永久终止循环。即不执行本次循环中break后面的循环语句,直接跳出循环,结束循环。
continue:是用于终止本次循环。即本次循环中continue后面的代码不执行,进行下一次循环的入口判断。
先来看看break运行结果
from math import sqrt
for n in range(10, 1, -1):
root=sqrt(n)
if root==int(root):
print(n)
break
else:
print("Didn't find it")
运行结果是
Python 3.9.0 (tags/v3.9.0:9cf6752, Oct 5 2020, 15:34:40) [MSC v.1927 64 bit (AMD64)] on win32
runfile(‘D:/python/pythonProject/2020-11-30学习内容.py’, wdir=‘D:/python/pythonProject’)
Didn’t find it
Didn’t find it
Didn’t find it
9
break 发现了平方数后就跳出循环,不在执行9以下数字的判断了。
看看continue运行结果
from math import sqrt
for n in range(12, 1, -1):
root=sqrt(n)
if root==int(root):
print(n)
continue
else:
print("Didn't find it")
Python 3.9.0 (tags/v3.9.0:9cf6752, Oct 5 2020, 15:34:40) [MSC v.1927 64 bit (AMD64)] on win32
runfile(‘D:/python/pythonProject/2020-11-30学习内容.py’, wdir=‘D:/python/pythonProject’)
Didn’t find it
Didn’t find it
Didn’t find it
9
Didn’t find it
Didn’t find it
Didn’t find it
Didn’t find it
4
Didn’t find it
Didn’t find it
continue 发现了平方数后就跳出本次循环,然后接着寻找9以下数字,直至循环条件结束。
这段代码明显的对比了break和continue的区别