Two pointers is a method for iterating over a linear collection, such as array list and string, by maintaining two indices instead of one to reduce the time complexity of the solution

Let's see a specific example

### The 2Sum Problem

Given an array of integers `A[N]`

and an integer number `targetSum`

Find if existing in `A`

two integers `A[i]`

and `A[j]`

such that `A[i] + A[j] = targetSum`

### Two pointers approach

```
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