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# Two Pointer Method

##                                            Two Pointer Method

![Various ways of using two pointer](https://1416717093-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-ME49AWTsL3PV5O3FW36%2F-ME8vLTXE9rXVyJww8nD%2F-ME94wXOOligqRUywLdr%2FArray_Basics_Conclusion_1.png?alt=media\&token=0ed093ec-420b-41cc-b08b-370cc4be917d)

This method is quite helpful in array's to do in-place operations and help us to save an extra space of O(n).

 **This technique can also be used to solve:**

* `Slow-pointer and fast-pointer problem in Linked List`
* `Sliding Window Problem`

**Iterate the array from two ends to the middle.**\
**One slow-runner and one fast-runner at the same time.**