需要更改正则表达式以获得其他后缀标准 [英] need to change regex for additional postfix criteria

问题描述

所以我有这个代码：

Pattern pattern = Pattern.compile("\\d*(\\s\\d+\\.)*\\s*[-\\+\\*/\\$£]");

String input = "4.0 5.0 2.0 / + 7.0 - 11.0 34.0 2.0 / 3.0 / 1.0 * +";
Matcher matcher = pattern.matcher(input);
List<String> output = new ArrayList<>();
while (matcher.find()) {
    output.add(matcher.group());
}

当我正在解析整数时，正则表达式当然没问题但是我现在需要它考虑到可以有一个。代表一个浮点。

When i was working on just parsing integers the regex was of course fine however i now need it to take into account that there can be a . to represent a floating point.

想知道是否有人可以帮我添加这个

Wondering if someone can help me with adding this in

预期输出应该是：

4.0 5.0 2.0 / 
+ 
7.0 - 
11.0 34.0 2.0 /
3.0 / 
1.0 * 
+

推荐答案

这将产生您想要的输出。逻辑OR | 运算符旁边的部分将匹配剩余的 [ - + * / $£] 符号子字符串。

This would produce the output you want. The part next to the Logical OR | operator will matches the [-+*/$£] symbols from the remaining sub-string.

Pattern pattern = Pattern.compile("\\d+(?:\\.\\d+)?(\\s\\d+(?:\\.\\d+)?)*\\s*[-+*/$£]|[-+*/$£]");

String input = "4.0 5.0 2.0 / + 7.0 - 11.0 34.0 2.0 / 3.0 / 1.0 * +";
Matcher matcher = pattern.matcher(input);
ArrayList<String> output = new ArrayList<String>();
while (matcher.find()) {
    output.add(matcher.group());
}
for (String s: output)
{
    System.out.println(s);
}

输出：

4.0 5.0 2.0 /
+
7.0 -
11.0 34.0 2.0 /
3.0 /
1.0 *
+

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