Comviva Technology Interview Questions and Answers for Freshers

Calculate the total amount of rainwater that can be trapped within given elevation map.

• Iterate through the array to find the maximum height on the left and right of each bar.

• Calculate the amount of water that can be trapped above each bar by taking the minimum of the maximum heights on the left and right.

• Sum up the trapped water above each bar to get the total trapped water for the elevation map.

Inheritance is a mechanism in OOP where a new class is derived from an existing class.

• Allows for code reusability and saves time

• Derived class inherits properties and methods of base class

• Can override base class methods in derived class

• Can have multiple levels of inheritance

• Example: class Dog extends Animal {}

Normalization is the process of organizing data in a database to reduce redundancy and dependency.

• 1NF (First Normal Form) - Each column in a table must have atomic values.

• 2NF (Second Normal Form) - A table must be in 1NF and all non-key attributes must be dependent on the primary key.

• 3NF (Third Normal Form) - A table must be in 2NF and all non-key attributes must be independent of each other.

• 4NF (Fourth Normal Form) - A table must be in 3NF and have no multi-valued dependenci...read more

Find the first character that repeats in a given string.

• Iterate through the string and keep track of characters seen so far.

• If a character is already seen, return it as the first repeating character.

• If no repeating character is found, return null.

Implement Merge Sort algorithm to sort a sequence of numbers in non-descending order.

• Divide the input array into two halves recursively until each part has a size of '1'.

• Merge the sorted arrays to return one fully sorted array.

• Time complexity of Merge Sort is O(n log n).

Count nodes within K-distance from marked nodes in a connected, undirected, acyclic graph.

• Create an adjacency list to represent the graph.

• Use BFS to traverse the graph and calculate distances from marked nodes.

• Keep track of visited nodes and distances to avoid revisiting nodes.

• Return the count of nodes with distances less than 'K' from all marked nodes.

• Handle edge cases like empty graph or marked nodes.

Given coin denominations and a target value, find the total number of ways to make change.

• Use dynamic programming to keep track of the number of ways to make change for each value up to the target value.

• Iterate through each denomination and update the number of ways to make change for each value.

• Handle base cases such as making change for 0 value.

• Consider all possible combinations of denominations to make change for the target value.

Count occurrences of a given integer in a sorted array.

• Use binary search to find the first and last occurrence of X in the array.

• Calculate the count by subtracting the indices of the last and first occurrences.

• Handle cases where X is not present in the array.