Numerify Interview Experience | Set 1 (On-Campus)

First written test was conducted on CoCubes platform,consisting of two parts: 
Part 1: Aptitude,Verbal, 
Part 2: 30 MCQ’s consisting of output questions of java,c++.Also from DBMS,CN,OS. 

Then after selection from written test,next round was Assignment round,we had to code in java or C++. 
1.Given is a (mxn) matrix with values comprising of 0 and 1. 1 defines a path while 0 is a 
void. By traversing from top (0,0) (top-left) position using up, right, down and left 
position, is it feasible to figure out if there is a valid path to the final (m-1, n-1) (bottomright) 
position. You cannot step on an already traversed tile more than once. If there is a 
valid path, can the same be printed?Print all possible 
paths. 
Input:

4,5
1,0,1,1,0
1,1,1,1,1
0,0,1,1,0
1,0,0,1,1

Output: 
Yes

[{(0,0), (1,0), (1,1), (1,2), (2,2), (2,3), (3,3),(3,4)},
{(0,0), (1,0), (1,1), (1,2), (1,3), (2,3), (3,3),(3,4)},
{(0,0), (1,0), (1,1), (1,2), (0,2), (0,3), (1,3), (2,3), (3,3), (3,4)}]

Interview Round:

Results of Assignment round were mailed to us and selected students were called for interview round. 
He started by discussing assignment question and variances of it,he asked approach to find the Shortest path in Assignment question. 
After this,he discussed on all my projects in detail which i had mentioned in my C.V. 
Then he gave me DBMS questions to solve one by one: 

1. Design a database schema to store Student marks for each test in the class per 
term. The information also should store the Professor who is in-charge to 
conduct that test. On this data, design a schema to secure data for view as 
follows: 
Professor can view data of all the students 
Student can view data pertaining to himself. 
Student can view Low, Average and High score of the class for each subject 
without the name of the student to compare his score with. 

2. He showed me two tables on laptop,First table with two cols:Boss_id,Emp_under_id. 
second table two cols:Emp_id,Designation. 
Write query to display hierarchy for any select employee based on designation,he asked what keys will you give to which cols and why?Explained the query. 

3. He asked there is large document given with lakhs of sentences, write a query to display count of corresponding each distinct word.(This was easy one). 

Other interviewer started asking Java Questions: 
1.Oops concepts explain with example inheritance,polymorphism. 
2.Abstraction,Data encapsulation why it is used. 
3.He asked in detail about Static keyword in java,what are static blocks why they are used. 
4.Why the signature of main method in java is (Public static void) and if you remove public/void/static what errors it will give. 
5.Diff btween threads and processes?Diff ways of creating threads in java? 
6.Explain multiThreading in java,he went into detail of this.He asked can you start a thread multiple number of times? 

Then he gave me very simple code to write: 
Given Slabs of percentages of tax,write a code to calculate tax for provided input: 
0-2lakhs–>3% 
2-5lakhs–>5% 
5-8lakhs–>7% 
above 8 lakhs–>12% 
He asked me to explain the code. 
Last question was a puzzle: 
Bridge and torch puzzle,There are four people who want to cross a bridge,and they have a single torch which they need to carry while crossing the bridge. 
Time taken by four people A,B,C,D is 2,2,5,5 mins respectively,to cross the bridge. When two people cross the bridge together, they must move at the slower person’s pace. 
Calculate minimum time needed for all four to be on the other side of bridge.