String s = e.nextLine();
String[] sa = s.split("+");
System.out.println(Arrays.toString(sa));
我的输入是“ 1 + 2 + 3”。正则表达式:“ +”给出悬挂的元字符错误。 是什么?
答案 0 :(得分:2)
正则表达式中的字符<body>
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<source src="video.mp4">
</video>
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<div class="d-none d-md-block d-lg-none embed-responsive embed-responsive-16by9 cab-video">
<video class="embed-responsive-item">
<source src="video.mp4">
</video>
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<source src="video.mp4">
</video>
</div>
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<div class="d-block d-sm-none embed-responsive embed-responsive-1by1 cab-video">
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<source src="video.mp4">
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</body>
是保留字符(表示“至少一个出现的先前写入的字符”)
要解决您的问题,您需要使用双反斜杠将其转义:+