American Express vs Oracle Interview Questions
American Express lists 23 LeetCode interview questions while Oracle lists 314. They share 10 problems — 43% of American Express's bank and 3% of Oracle's. Focus on the overlap first, then drill into 13 American Express-only and 304 Oracle-only questions.
Overview
Preparation Strategy
Step 1 — Shared core: Solve the 10 overlapping problems first. These are the highest-yield questions for candidates interviewing at both American Express and Oracle.
Step 2 — Company-specific depth: Add American Express-specific problems like Minimum Deletions to Make Character Frequencies Unique, Maximum Equal Frequency, Divide an Array Into Subarrays With Minimum Cost II and Oracle-specific problems from the exclusive lists below.
Step 3 — Difficulty tuning: Oracle skews harder in our data. Budget extra time for Hard problems if you are targeting that company.
Difficulty Comparison
Top Shared Topics
10 Shared Questions
High-priority problems to practice for both American Express and Oracle.
| Problem | Difficulty |
|---|---|
| Two Sum | Easy |
| Valid Anagram | Easy |
| Longest Substring Without Repeating Characters | Medium |
| Best Time to Buy and Sell Stock | Easy |
| 3Sum | Medium |
| Rotate Array | Medium |
| Permutations | Medium |
| Isomorphic Strings | Easy |
| Linked List Cycle II | Medium |
| Longest Common Prefix | Easy |
Unique to American Express (13)
Problems in American Express's list that do not appear at Oracle.
Unique to Oracle (304)
Problems in Oracle's list that do not appear at American Express.
| Problem | Difficulty |
|---|---|
| LRU Cache | Medium |
| Number of Islands | Medium |
| Group Anagrams | Medium |
| Top K Frequent Elements | Medium |
| Sliding Window Maximum | Hard |
| Valid Parentheses | Easy |
| Merge k Sorted Lists | Hard |
| Merge Intervals | Medium |
| Meeting Rooms II | Medium |
| Longest Palindromic Substring | Medium |
| Spiral Matrix | Medium |
| Minimum One Bit Operations to Make Integers Zero | Hard |
Frequently Asked Questions
How many LeetCode questions do American Express and Oracle share?
American Express and Oracle share 10 LeetCode interview questions. 13 problems appear only in American Express's list and 304 appear only in Oracle's list.
What topics overlap most between American Express and Oracle?
The most common shared topics between American Express and Oracle are Array (6 shared questions), Hash Table (5 shared questions), String (4 shared questions), Two Pointers (3 shared questions), Sorting (2 shared questions). Mastering these areas prepares you for both companies.
Which company asks harder LeetCode questions: American Express or Oracle?
American Express has 8 Easy, 12 Medium, and 3 Hard questions. Oracle has 61 Easy, 194 Medium, and 59 Hard questions. Oracle has a higher proportion of Hard problems in its interview set.
How should I prepare if interviewing at both American Express and Oracle?
Start with the 10 shared problems since they cover what both companies ask most often. Then add 13 American Express-specific and 20 Oracle-specific questions to round out your prep.