MIXTURES - spoj

#1

Question link: https://www.spoj.com/problems/MIXTURES
Answer: https://ide.codingblocks.com/s/48539

Please check it is giving null pointer exception

#2

Hey @Vidushi04
Your approach to the question is not right.
A null pointer exception is thrown when an application attempts to use null in a case where an object is required. These include: Calling the instance method of a null object. Accessing or modifying the field of a null object.

I am sharing my code for your ease so that you get to the right direction.
https://ide.codingblocks.com/s/48723

I have included all the 3 approaches in the code namely, recursion, Top-down DP and Bottom-Up DP. This would help you in learning and revising the concepts very well. Take help from it and then try to code it yourself.

Hope it helps! :relaxed:

#3

Thank you so much sir
Sir please tell me where I was calling the instance of null object.
There can be only one chance when base case is hit, so at base case I made the instance values either 0 or max

#4

Try debugging your code using the debugger in Eclipse ide. That would also help you know and learn your mistake. Yes, the problem lies due to base case and when n is negative.
And learn the DP-dynamic programming approach for such questions. That is the best and most efficient approach.