adding optimized code for largest rectangle histogram

[Avnee29]

Feature description

You are given an array of integers heights where heights[i] represents the height of a bar. The width of each bar is 1.

Return the area of the largest rectangle that can be formed among the bars. giving optimized solution for this problem using stacks
kindly assign me this issue

[rushikeshkotkar04]

I'm working on this Feature