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Code Problem / Data Structures and Algorithms / Recursion (32)
Code Problem / Data Structures and Algorithms / Binary Search (30)
Code Problem / Data Structures and Algorithms / Linked Lists (26)
Code Problem / Data Structures and Algorithms / Backtracking (26)
Code Problem / Data Structures and Algorithms / Stacks and Queues (25)
Code Problem / Data Structures and Algorithms / Hashing (24)
Databases / SQL / Backup and Recovery (19)
Code Problem / Data Structures and Algorithms / Arrays and Strings (19)
Databases / SQL / Database Normalization (18)
Code Problem / Data Structures and Algorithms / Time Complexity (17)
Databases / SQL / Locking (16)
Databases / SQL / Replication (15)
Databases / SQL / SQL Queries (13)
Code Problem / Data Structures and Algorithms / Graphs (13)
Databases / SQL / Database Security (13)
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A system that can automatically detect plagiarism in documents is needed.
About this solution: The candidate's solution demonstrates a level of completeness and solves the problem. The general approach is efficient and would work well in practice.
To find the sum of all elements in an array, simply iterate through the array and add each element to a total sum.
About this solution: The candidate's solution is correct and demonstrates a level of completeness. The candidate's approach is clear and understandable.
None
About this solution: The candidate's solution is complete and solves the problem. The candidate's approach is to first find the adjacency matrix A, then the matrix giving the number of 3 step walks, then the generating function for walks from point i → j, and finally the generating function for walks from points 1 → 3.
Databases / SQL
SQL
This technical problem deals with creating a function that will take in an array of integers and return the sum of all the even numbers in the array.
About this solution: The candidate's solution is correct and demonstrates a level of completeness. The candidate's approach is also optimal, making use of a CASE statement to check if the number is even and then returning the number if it is even and 0 if it is not. The SUM function then adds up all the numbers in the column.
This problem asks whether a given singly linked list is a palindrome. A palindrome is a word, phrase, or sequence that reads the same backward as forward. In this case, the list is a palindrome if the elements in the list read the same forward as backward.
About this solution: The candidate's solution correctly checks if a singly linked list is a palindrome. The approach is to use a slow and fast pointer to find the middle of the list, reverse the second half of the list, and then compare the two halves.
One potential improvement to the solution would be to use a stack to keep track of the first half of the list instead of reversing the second half. This would avoid having to reverse the second half of the list, which is unnecessary work.
This problem requires the use of a binary search algorithm to find a target value in a sorted array. If the target value is found, the index of that value is returned. If the target value is not found, -1 is returned.
About this solution: The candidate's solution is complete and solves the problem. The candidate uses a binary search, which is the most efficient way to search a sorted array.
Databases / SQL
SQL
This problem deals with using a cursor to loop through a table of employee data in order to print the employee's name and salary.
About this solution: The candidate's solution is complete and solves the problem. The candidate has used a cursor to loop through the table and print the employee's name and salary. This is the optimal solution.
This problem involves searching for a given value in a sorted array of integers. If the value is found, the index of the target value is returned; if not, -1 is returned.
About this solution: The candidate's solution is correct and demonstrates a level of completeness. The candidate has correctly identified the problem and has provided a solution that solves the problem. The candidate's approach is general and uses a binary search algorithm, which is the optimal solution for this problem.