2013-12-16 34 views

回答

5
perl -E 'say rindex("bar foo bar foo", "foo")' 
           ^__ found first substring from right side 
12 

perl -E 'say index("bar foo bar foo", "foo")' 
         ^__ found first substring from left side 
4 
+1

请评论向下票 –

+0

什么两者的区别? – user3098497

+0

这里我们必须声明子字符串? – user3098497