检查项目是否在列表中的简单方法？ [英] Easy way to check if item is in list?

问题描述

我在C ++中编写一个搜索算法，我需要做的一件事是有一些if语句检查上面，下面，左边和右边的单元格。

I'm writing a search algorithm in C++, and one of the things I need to do is have a few if statements that check cells above, below, left of, and right of.

每次发现单元格被打开并添加到堆栈中时，我想将它添加到已经选中的单元格列表中。

Each time a cell is found to be open and added to the stack, I want it added to a list of cells already checked.

I想要能够在if语句中 if（thisCell不在checkedCells中）。

I want to be able to say in the if statement if(thisCell is not in checkedCells).

任何简单的想法？

谢谢！

推荐答案

std :: set 容器，因为它提供了搜索项比列表更快的能力。然后你可以写：

For this purpose it's better to use the std::set container, because it provides you with the ability to search for items faster than a list. Then you can write:

std::set<itemType> myset;
...

if (myset.find(item) != myset.end()) {
  // item is found
}

Google可以找到更大的示例。例如，此处。

A larger example can be found by googling. For example, here.

这篇关于检查项目是否在列表中的简单方法？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！