Oracle Interview | Set 12 (On Campus for Application Dev Profile)

This is not just my interview. But just gathered some questions asked to other candidates also.

Round 1 –
1) 25 Horses puzzle where you to find top 5 horses. Answer : 8
2) Two sand timers which measure 11,7 minutes.You have to measure 15min using those.
3) Given 4 pairs of socks one of each yellow,blue,black,green.You have arrange them in such a way that there are 4 socks in between yellow socks ,3 in between the blue socks,2 in between the black and 1 in between the green socks.
4) Given weighing scale.Find defective ball out of 27 balls in minimum number of comparisons.You will also have to tell whether defective ball is lighter or heavier.
5) 100 floors – 2 eggs puzzle.
6) 2 ropes which can be burnt in 20min each.Have to measure 15min using those.

Round 2 –
Talked about resume,projects.
1) Reverse a string,number.
2) Reverse number using recursion.
3) Coin change – DP
4) Given a string count all different palindrome strings possible of any length and from each and every permutation of given string. Ex: Given TACKLE – all palindrome strings of length 1,2,3… from TACKLE , ACKLET, CKEATL ,ETALKC etc.
5) A 3×3 matrix with all distinct integers 1-9. How many combinations of matrix such that 3 digit number in first row when multiplied by 2 represents number in row 2 and when multiplied by 3 represents number in row 3.
6) Repeating elements in a integer array.
7) Left view of a tree.
8) Given a sudoku (a 9×9 matrix) .In single iteration you will to tell if it is solved or not.
9) Data Structure used for implementation of dictionary.
10) Given 2 dates.have to find number of days between them.