Paytm Interview Experience | Set 14 (For Senior android Developer)

Last Updated : 23 Jul, 2025

Senior android Developer

Coding Round:
1. Spirally traversing a matrix
2. Longest Increasing Subsequence
First Round:
1. find "longest line" of 1's in array. Hoizontal and Vertical. Array is made only of 0's and 1's, and looks for example like this: 4 4 0 1 1 1 0 1 0 1 0 1 1 0 1 0 1 0
2. 2D Array is made only of 0's and 1's, you have to find number of island.
Second Round:
1. Some Android question / Some java questions basic
2. Sort an array of 0s, 1s and 2s
3. Check if string are palindrome.
Third Round:
1. Design the architecture of Paytm market place.
2. Some random questions on Java like threading, collections, hashmap etc.
3. Why HashTable not allow NULL but Hashmap allow.
4. Array question of finding mission number. etc
Fourth Round:
1. Singleton patterns
2. Design your own Arraylist.
3. Sorting of linkedlist.
4. Program for array rotation
5. LRU cache
6. Recycler view vs list view.
7. Services, Fragment, app optimization, retainInstance() in fragment, Asynctaskrotation problem etc
8. Graph traversal for circular loop example.
9. Find max of Stack optimize way.

URL: https://www.geeksforgeeks.org/interview-experiences/paytm-interview-experience-set-14-for-senior-android-developer/