SDE - 1

You are given an array Arr consisting of n integers, you need to find all the distinct triplets present in the array which adds up to zero.

An array is said to have a triplet {arr[i], arr[j], arr[k]} with 0 sum if there exists three indices i, j and k such that i!=j, j!=k and i!=k and arr[i] + arr[j] + arr[k] = 0.

Note :

1. You can return the list of values in any order. For example, if a valid triplet is {1, 2, -3}, then (2, -3, 1), (-3, 2, 1) etc is also valid triplet. Also, the ordering of different triplets can be random i.e if there are more than one valid triplets, you can return them in any order.
2. The elements in the array need not be distinct.
3. If no such triplet is present in the array, then return an empty list, and the output printed for such a test case will be "-1".

You're given a string 'STR' containing ‘0’, ‘1’ and ‘?’ special characters. Your task is to generate all the strings that are possible by replacing the special character ‘?’, with either of the characters ‘0’ or ‘1’.

You are given an arbitrary binary tree consisting of N nodes where each node is associated with a certain integer value from 1 to 9. Consider each root to leaf path as a number.

For example:

       1
      /  \
     2    3

The root to leaf path 1->2 represents the number 12.
The root to leaf path 1->3 represents the number 13.

Your task is to find the total sum of all the possible root to leaf paths.

In the above example,

The total sum of all the possible root to leaf paths is 12+13 = 25

Note:

The output may be very large, return the answer after taking modulus with (10^9+7).

What are the different operating systems? (Learn)

Batched operating systems
Distributed operating systems
Timesharing operating systems
Multi-programmed operating systems
Real-time operating systems

Write an SQL query to fetch records that are present in one table but not in another table.

SELECT * FROM EmployeeSalary
MINUS
SELECT * FROM ManagerSalary;