> For the complete documentation index, see [llms.txt](https://mqjyl2012.gitbook.io/algorithm/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mqjyl2012.gitbook.io/algorithm/classical-problem/expression-evaluation.md).

# 表达式求值

表达式求值是栈的一个重要的应用。表达式的表示方法主要有中缀表示法、前缀表示法和后缀表示法。其中前缀表达式又叫做**波兰表达式**，后缀表达式又叫做**逆波兰表达式**。

* 前缀转中缀，中缀转前缀
* 中缀转后缀，后缀转中缀
* 前后缀之间的相互转换可以用中缀作为中转来解决，或者也可以构造语法树遍历来解决。
* 前缀表达式求值，后缀表达式求值，中缀表达式求值比较简单

### :pen\_fountain: 前缀 <--> 中缀

### :pen\_fountain: 后缀 <--> 中缀

### :pen\_fountain: 构造语法树

### :pen\_fountain: 表达式求值

### :pen\_fountain: 相关题型


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