Paxcom India Software Developer Interview Questions and Answers

Count occurrences of a digit in a given range.

• Iterate through the range [A, B] and count occurrences of digit K.

• Convert integers to strings for easier digit comparison.

• Handle edge cases like when A or B is equal to K.

• Optimize by considering the position of K in the range.

Given an array of unique integers with two missing numbers, identify and return the missing numbers.

• Iterate through the array and mark the presence of each number in a separate array.

• Find the missing numbers by checking which numbers are not present in the marked array.

• Return the missing numbers in increasing order.

Find the missing integer in binary form from an array of unique binary strings.

• Iterate through the binary strings and convert them to integers.

• Calculate the sum of all integers from 0 to N using the formula (N*(N+1))/2.

• Subtract the sum of integers in the array from the total sum to find the missing integer.

• Convert the missing integer to binary form and return it as a string.

Find the maximum area of an island in a grid of 0s and 1s.

• Iterate through the grid and perform depth-first search (DFS) to find connected 1s.

• Keep track of the area of each island found and return the maximum area.

• Consider all four directions (horizontal, vertical, and diagonal) while exploring the island.

• Handle edge cases like grid boundaries and already visited cells during DFS.

• If no island is present, return 0 as the maximum area.

Reverse a given string containing alphabets, numbers, and special characters.

• Iterate through the string from the end to the beginning and append each character to a new string.

• Alternatively, you can use built-in functions like reverse() or slicing in some programming languages.

• Remember to handle different types of characters like alphabets, numbers, and special characters.

• Ensure to consider the constraints on the input size and number of test cases.

The task is to find the frequency of each character from 'a' to 'z' in a given string.

• Create an array of size 26 to store the frequency of each character from 'a' to 'z'.

• Iterate through the string and increment the count of the corresponding character in the array.

• Print the array of frequencies as the output for each test case.