Associate Software Engineer

Approach :
1) I solved it in O(N^2) approach.
2) Sort the array.
3) Initially map all the elements of the array to their index in a Hash Map or a Hash Set.
4) Now , run 2 for loops and for every x^2 + y^2 ,check if there exists a z^2 s.t x^2+y^2=z^2 and the index of z^2 is
different than both the indices of x and y.

Approach :
1) Calculate the length of both the lists, say len1 and len2

2) Get the absolute difference of the lengths, diff = |len1 – len2|

3) Now traverse the long list from the first node till ‘diff’ nodes so that from there onwards both the lists have equal
number of nodes

4) Then traverse both the lists in parallel and check whether a common node is reached (Note that getting a common
node is done by comparing the address of the nodes, not the data)
4.1) If yes, return that node’s data
4.2) If no, return -1


TC : O(N) , where N = max length of the linked list
SC : O(1)