InterviewBit Problems   Swap List Nodes in pairs : Unsolved

About the Swap List Nodes in pairs : Unsolved category (1)
Stupid question took me over 2 hrs(copied from gfg) (2)
Easy solution using three pointer approach (1)
Easy Solution with O(n) time complexity (2)
Easy CPP solution 0(n) (1)
Smallest and easisest C++ code. (5 lines) (3)
Modified version of similar problem (1)
C++ Easy Approach O(n) Time, and O(1) Space; (1)
Odd number of elements (2)
What is the problem in this code ? Please help (1)
VV Easy to understand C++ soln (1)
Just read before start (3)
What the problem in this code? (2)
Though it says O(1) space, recursive solution got accepted (4)
What is wrong with this code? Please help (2)
Python solution wenja easy (1)
Swift has test case input ptoblem. Do try to work in swift (1)
Unable to identify error in the code (3)
What is error in this code (1)
Tried the 1->2->3->4 and the output its not the correct answer (3)
This question has to be solved in what time complexity . it says time limit eexce (2)
Why memory limit is 80 MB when only constant space is allowed? While in Memory co (2)