American Express SDE-2 Interview Questions and Answers

Round duration - 80 minutes
Round difficulty - Medium

Q1. 
Longest Increasing Path in Matrix Problem Statement
Given a 2-D matrix mat with 'N' rows and 'M' columns, where each element at position (i, j) is mat[i][j], determine the length of the longest increasing...read more
Ans. 
The problem involves finding the length of the longest increasing path in a 2-D matrix starting from a given cell.
• Use dynamic programming to keep track of the longest increasing path starting from each cell.

• Implement a recursive function to explore all possible paths from a cell.

• Update the length of the longest path for each cell based on the maximum path length from its neighbors.

• Consider edge cases such as boundary c...read more
Answered by AI
Add your answer

Round duration - 50 minutes
Round difficulty - Hard

It was purely Data Structures and Maths.

Q1. 
Arithmetic Progression Queries Problem Statement
Given an integer array ARR of size N, perform the following operations:
- update(l, r, val): Add (val + i) to arr[l + i] for all 0 ≤ i ≤ r - l.
- rangeSu...read more
Ans. 
Implement update and rangeSum operations on an integer array based on given queries.
• Implement update(l, r, val) by adding (val + i) to arr[l + i] for all i in range (0, r - l).

• Implement rangeSum(l, r) to return the sum of elements in the array from index l to r.

• Handle queries using 1-based indexing.

• Ensure constraints are met for input values.

• Output the sum of arr[l..r] for each rangeSum operation.
Answered by AI
Add your answer

Round duration - 70 Minutes
Round difficulty - Easy

Round duration - 30 Minutes
Round difficulty - Easy

Q1. 
Pattern Matching Problem Statement
Given a pattern as a string and a set of words, determine if the pattern and the words list align in the same sequence.
Input:
T (number of test cases)
For each test ca...read more
Ans. 
The problem involves determining if a given pattern aligns with a list of words in the same sequence.
• Iterate through the pattern and words list simultaneously to check for matching sequences.

• Use a hashmap to store the mapping between characters in the pattern and words in the list.

• Compare the mappings to determine if the pattern and words align in the same sequence.
Answered by AI
Add your answer

DSA, Leetcode medium -2 problems

Q1. Easy Leetcode Problem: Count of substrings with no repeating characters
Ans. 
Count substrings with unique characters in a given string
• Use a sliding window approach to keep track of unique characters in a substring

• Use a set to store characters in the current window and update the window accordingly

• Increment the count of valid substrings whenever a new character is added to the set
Answered by AI
Add your answer
Q2. Debugging a Java Code
Ans. 
Debugging a Java code involves identifying and fixing errors in the code to ensure it runs correctly.
• Start by understanding the error message or symptoms of the issue.

• Use debugging tools like breakpoints, watches, and logging to track the flow of the code.

• Review the code logic and check for common mistakes like typos, incorrect variable assignments, or logic errors.

• Test different scenarios to reproduce the issue and na...read more
Answered by AI
Add your answer

Q1. Design Parking System
Ans. 
Design a parking system with different types of parking spots
• Create classes for different types of parking spots (e.g. compact, regular, handicap)

• Implement methods for checking availability, reserving, and releasing spots

• Consider implementing a parking lot class to manage all parking spots
Answered by AI
Add your answer