Goldman Sachs Interview Experience for Software Developer Hiring(Java)

So I have around 1.6 years of experience in Java. I was contacted by the GS HR when she saw my profile on naukri.com. Round 1: HackerRank Test

1. Find number of Positional Elements
2. Suppose a String s = "kite". We can represent it as "119205" by considering the position of each alphabet as it comes in A-Z(like 1 for A, 2 for B, ........, 11 for K and so on). But it is also possible that the string "119205" can be formed by the word "aaite" and "aste". So given a string of integer we have to find how many such words are possible.

   Sample Input: "2112"
   Output: 5

   Explanation:

   2112 can be represented as:
   (2)(1)(1)(2) ->baab
   (2)(1)(12) ->bal
   (2)(11)(2)->bkb
   (21)(1)(2)->uab
   (21)(12)->ul

Round 2: CoderPad Round Two Easy questions:

1. Given an array in which there are arrays that are of length two, the first index of that array has the student name and the second index has the marks scored. Find the maximum average scored by any student. The array can have multiple subjects of marks for a particular student.
2. Suppose we are given a string "aaabbbbbccccdaa", then we to print "a3b5c4d1a2".

Round 3: Telephonic Now this round was tricky for me initially which includes the interface concepts. But in the second half of the interview, I was able to answer many of the questions like.

1. What is method overloading and overriding,
2. How HashMap map works internally(Explained the full concept with bucket implementation).
3. A puzzle in the end which when I was telling him how I will go through it he knew I will solve it so he said no need to do I got your thinking.
4. Difference between checked and unchecked exceptions.
5. What is the diff between Array and ArrayList

Now the question which decided my fate, this was asked in the starting actually. Suppose there are Two Interface A and B, both have one function which is totally same no difference, if you implement both the interface in a class, then what will happen. Here I was confused because I never came across this situation, and then after that, he kept stretching this topic and kept asking me in-depth. Discussion on this topic went for around 30-35 mins.   In between the interview if you say something then they will ask that are you sure that this answer is right, be firm to your answer if you are confident. They will try to confuse you. Got Eliminated here : (