代码:
import string
n=input()
for i in n:
if i in string.ascii_lowercase:
print(i.upper(),end='')
elif i in string.ascii_uppercase:
print(i.lower(),end='')
else:
print(i,end='')
结果:

代码:
import string
n=input()
for i in n:
if i in string.ascii_lowercase:
print(i.upper(),end='')
elif i in string.ascii_uppercase:
print(i.lower(),end='')
else:
print(i,end='')
结果: