10+ Paytm Software Developer Intern Interview Questions and Answers

Reorder array to avoid odd numbers at even indices and even numbers at odd indices.

• Swap odd numbers at even indices with the nearest odd number at an odd index.

• Swap even numbers at odd indices with the nearest even number at an even index.

• Maintain counts of odd and even numbers to ensure equal distribution.

Find all occurrences of a given string in a matrix in all eight possible directions.

• Iterate through each cell in the matrix and check for the starting character of the word.

• For each starting character found, check in all eight directions for the complete word.

• Keep track of the coordinates of each character in the word for each occurrence.

• Print the coordinates of each character for all occurrences found.

• If no occurrences are found, output 'No match found'.

Find the diagonal traversal of a binary tree of integers.

• Traverse the binary tree diagonally using a queue and a map to store nodes at each diagonal level.

• Use a depth-first search approach to traverse the tree and populate the map with nodes at each diagonal level.

• Iterate through the map to get the diagonal traversal of the binary tree.

Given stock prices for 'N' days, find maximum profit with up to two buy-and-sell transactions.

• Iterate through the array of stock prices to find the maximum profit with two transactions

• Keep track of the maximum profit by considering all possible buy and sell combinations

• Ensure to sell the stock before buying again to maximize profit

Find the length of the smallest subarray in a given array with sum greater than a given value.

• Iterate through the array while keeping track of the current subarray sum.

• Use two pointers technique to find the smallest subarray with sum greater than X.

• Update the minimum subarray length as you iterate through the array.

• Return the length of the smallest subarray found.

• Example: For ARR = [1, 2, 21, 7, 6, 12] and X = 23, the output is 2.

Find the Next Greater Element for each element in a list of integers.

• Iterate through the list of integers from right to left.

• Use a stack to keep track of elements for which the Next Greater Element is not yet found.

• Pop elements from the stack until a greater element is found or the stack is empty.

• Assign the Next Greater Element as the top element of the stack or -1 if the stack is empty.

Given a binary tree, a target node, and an integer K, find all nodes at distance K from the target node.

• Traverse the binary tree to find the target node.

• From the target node, perform a depth-first search to find nodes at distance K.

• Use a recursive function to keep track of the distance from the target node.

• Return the values of nodes found at distance K in any order.

The task is to find the diameter of a binary tree, which is the longest path between any two nodes in the tree.

• Traverse the tree to find the longest path between any two nodes.

• Keep track of the maximum diameter found during traversal.

• The diameter may not necessarily pass through the root node.

• Consider both left and right subtrees while calculating the diameter.

• Example: For input '1 2 3 4 -1 5 6 -1 7 -1 -1 -1 -1 -1 -1', the diameter is 6.

Given an array of integers and a target, find all pairs of elements that add up to the target.

• Iterate through the array and for each element, check if the target minus the element exists in a hash set.

• If it does, add the pair to the result. If not, add the element to the hash set.

• Handle cases where the same element is used twice in a pair.

• Return (-1, -1) if no pair is found.

Encrypt each digit in a numeric string by replacing it with its encrypted equivalent.

• Iterate through each character in the string and replace it with its encrypted equivalent

• Use a mapping to determine the encrypted equivalent of each digit

• Return the encrypted string for each test case