问一个正则的问题，大神不要笑我哈~~~ - V2EX

问一个正则的问题，大神不要笑我哈~~~ - V2EX

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这是一个创建于 3422 天前的主题，其中的信息可能已经有所发展或是发生改变。

s='abbbc'
使用 ab*?，为啥结果是 a ？不是 ab 吗？

2 条回复 2016-06-22 10:20:27 +08:00

1

UnisandK

2016-06-22 10:10:23 +08:00

1

b*表示任意次数，?是懒惰匹配让次数最小，所以就变成 0 次了

2

codeek

2016-06-22 10:20:27 +08:00 via Android

1

正则表达式默认是贪婪匹配(最长匹配)，*？就开启了最短匹配，这里，也就是 0 个 b 了。

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