Tata Projects Interview Questions and Answers

Find minimum arrows needed to burst balloons in decreasing order of height

• Sort the array in decreasing order of height

• Initialize arrow count to 1 and max height to first balloon height

• Iterate through the array and if current balloon height is greater than max height, increment arrow count and update max height

• Return arrow count

• Time complexity: O(nlogn) for sorting, O(n) for iteration

• Space complexity: O(1)

The maximum length of the alternating sequence is returned along with the sequence itself.

• Iterate through the array and check if each element alternates with the previous one.

• Keep track of the current alternating sequence length and the maximum length seen so far.

• If the current element breaks the alternating pattern, update the maximum length and reset the current length.

• Print the alternating sequence by storing the elements in a separate array.

The answer is a letter in the string that appears most frequently.

• Iterate through each letter in the string and count its frequency

• Keep track of the letter with the highest frequency

• Return the letter with the highest frequency

Given a binary matrix, find the largest square containing only 1's and return its area.

• Use dynamic programming to solve the problem

• Create a 2D array to store the maximum size of square at each point

• For each point, check the top, left, and diagonal top-left values to calculate the maximum size of square

• Return the maximum size of square found

Using a copy constructor in C++ creates a new object by copying the values of another object.

• Copy constructor is a special member function that creates a new object as a copy of an existing object.

• It is invoked when a new object is created from an existing object.

• Example: MyClass obj1; MyClass obj2 = obj1; // Copy constructor is called to create obj2 as a copy of obj1.

Pointers/references are used to pass memory addresses instead of values, for efficiency and to modify data directly.

• Use pointers when you need to modify the original data passed to a function

• Use references when you want to avoid copying large data structures

• Pointers are commonly used in dynamic memory allocation

• References are used in function parameters to avoid unnecessary copying

• Example: int x = 10; int *ptr = &x; *ptr = 20; // changes the value of x to 20