1. Implement MaxQueue ( like Min Stack)..with Find Max to be done in O(1).... couldn't solve
2. Check if Binary Tree is a complete BT
3. K closest points to origin on a 2D plane
4. Moving window anagram substring problem
5. Dot product of sparse matrices

Solved 4/5
System design also went ok I guess ( Design privacy options of FB posts)

Is there any chance?
or do they need all 5 questions solved to even consider?