c++ - STL iterators - purpose -

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What is the purpose of STL iterations? Why did the programmer create this concept?

The iterators allow you to separate the algorithm from the container. As long as you have a start and end iterator, and know the ability of the iterator (random access etc), you can work on the specified range by iterators. For example, see std :: for_each , std :: transform . In this way, you can apply only one version of the algorithm on which you want to operate it, instead of needing to write a new one for each container.


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