Two Pointer Method
The two pointers method uses two indices(pointers) to traverse through a data structure(mainly arrays or strings) efficiently.
It is used to reduce the Time and space complexities of problems.
If brute force method uses O(n²) time complexity, two pointers method solves it in O(n).
There are 3 variations :
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1. Converging Pointers
2. Parallel Pointers( Sliding Window)
3. Trigger-based Pointers
Now let’s dive into Converging pointers :
This approach uses two pointers:
left → starts from the beginning
right → starts from the end
How it works:
Check the condition using left and right
1. If the condition is satisfied → return the result
2. If the value is less than required → increment the left pointer
3. If the value is greater than required → decrement the right pointer
