InterviewBit Problems   2 Sum : Solved

About the 2 Sum : Solved category (1)
C++, super simple algorithm (1)
When i use unordered_map in my dev c++ compiler its showing this: #error This fil (6)
Easy C++ solution using simple logic (1)
Very Easy short 4 liner (2)
Solution in O(n) space and O(n) time using unordered map in one loop (5)
Check out my soln (1)
I don't understand how my solution is different than the editorial or the fastest python code (1)
Simple easy to understand cpp code (1)
Simple Java Solution 2 Sum (3)
Simple iterative C++ solution using Map (1)
Simple solution with unordered_map (1)
Easy To Understand intuitive C++ Solution (1)
Python Solution more efficient then Editorial (3)
O(n) solution using unordered_map (4)
How much time do u took to solve it (1)
Easy O(n) Sol Cpp using Unordered Set (1)
C++ solution using multimap for optimization (nlogn) (1)
My solution using Unordered Map (1)
O(n) Solution using Unordered map (1)
O(n) using unorderd_map & unordered set (1)
Is there any way to overcome O(n^2) (2)
Can someone explain the editorial solution to me? (2)
Inadequate test cases (1)