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单选题

判断char型变量c是否为小写字母的正确表达式是

A
'a'<=c<='z'
B
(c>=A) &&(c<=z)
C
('a'>=c) | | ('z'<=c)
D
(c>='a') &&<c<='z')

题目答案

D

答案解析

字符型数据在计算机内部是以 ASCII码存储的,英文大写字母和小写字母在ASCII码表中都是连续的。大写字母A~Z是从65~90,小写字母a~z是从97~122。所以只要变量c大于等于a并且小于等于z就能保证其为小写字母。
举一反三

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