Entry-Level & New Grad Interview Prep

This guide is for: Recent grads, bootcamp completers, career switchers, or anyone with less than 2 years of professional experience.

Time budget: 2–3 weeks, ~2 hours/day

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What Interviewers Expect at This Level

Entry-level interviews are not about being a 10× engineer. They're about proving you can learn quickly, write correct code, and work with a team. Here's the honest breakdown:

What they test	What they're really asking
DSA fundamentals	Can you solve structured problems with basic data structures?
Code quality	Do you write readable, working code — not just pseudo-code?
Communication	Do you think out loud and ask good clarifying questions?
Coachability	When given a hint, do you take it productively?
Attitude	Are you curious, humble, and eager to grow?

What they are NOT looking for:

• Optimal solutions on the first attempt (hints are expected)
• Deep system design knowledge
• 5 years of experience
• A flawless performance

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The 2-Week Study Plan

Week 1 — Foundations

Days 1–2: Arrays & Strings (the most common topic)

• Traversal, two-pointer technique, reversals
• String manipulation: reversals, palindromes, anagrams
• Hash maps for counting/lookup

Practice problems:

• LeetCode 1 — Two Sum ⭐
• LeetCode 242 — Valid Anagram
• LeetCode 125 — Valid Palindrome
• LeetCode 217 — Contains Duplicate
• LeetCode 121 — Best Time to Buy and Sell Stock

Days 3–4: Linked Lists & Stacks/Queues

• Traversal, reversal, finding the middle
• Detecting cycles
• Stack: valid parentheses pattern

Practice problems:

• LeetCode 206 — Reverse Linked List ⭐
• LeetCode 21 — Merge Two Sorted Lists
• LeetCode 141 — Linked List Cycle
• LeetCode 20 — Valid Parentheses ⭐
• LeetCode 232 — Implement Queue using Stacks

Days 5–6: Trees (very frequently asked)

• Binary tree traversals (in/pre/post/level-order)
• Height, depth, balance
• BFS pattern for level traversal

Practice problems:

• LeetCode 104 — Maximum Depth of Binary Tree ⭐
• LeetCode 226 — Invert Binary Tree
• LeetCode 100 — Same Tree
• LeetCode 102 — Binary Tree Level Order Traversal
• LeetCode 543 — Diameter of Binary Tree

Day 7: Review + Mock

• Re-solve your hardest problem from the week without looking at notes
• Time yourself: 35 minutes per problem

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Week 2 — Patterns + Interview Simulation

Days 8–9: Sliding Window & Binary Search

// Sliding window template
function maxSumSubarray(arr, k) {
  let windowSum = 0, maxSum = -Infinity;
  for (let i = 0; i < arr.length; i++) {
    windowSum += arr[i];
    if (i >= k) windowSum -= arr[i - k];
    if (i >= k - 1) maxSum = Math.max(maxSum, windowSum);
  }
  return maxSum;
}

// Binary search template
function binarySearch(arr, target) {
  let left = 0, right = arr.length - 1;
  while (left <= right) {
    const mid = Math.floor((left + right) / 2);
    if (arr[mid] === target) return mid;
    if (arr[mid] < target) left = mid + 1;
    else right = mid - 1;
  }
  return -1;
}

Practice problems:

• LeetCode 3 — Longest Substring Without Repeating Characters ⭐
• LeetCode 704 — Binary Search
• LeetCode 153 — Find Minimum in Rotated Sorted Array

Days 10–11: Recursion & Basic DFS

// Recursion pattern: think base case first
function fib(n) {
  if (n <= 1) return n;          // base case
  return fib(n - 1) + fib(n - 2); // recursive case
}

// DFS on grid
function dfs(grid, r, c) {
  if (r < 0 || r >= grid.length || c < 0 || c >= grid[0].length) return;
  if (grid[r][c] !== '1') return;
  grid[r][c] = '0'; // mark visited
  dfs(grid, r + 1, c); dfs(grid, r - 1, c);
  dfs(grid, r, c + 1); dfs(grid, r, c - 1);
}

Practice problems:

• LeetCode 200 — Number of Islands ⭐
• LeetCode 695 — Max Area of Island
• LeetCode 733 — Flood Fill

Days 12–13: Behavioral Prep

At entry level, behavioral interviews are mainly about your projects and learning ability. Prepare 3–5 stories using STAR:

Story	What to cover
Best project	What you built, your specific contribution, challenges overcome
A bug you fixed	How you debugged it, what you learned
Working with others	Collaboration, asking for help, code review
Learning something new	How you pick up new technologies
A failure or mistake	What went wrong, what you'd do differently

Entry-level behavioral question bank:

• "Tell me about yourself." (Practice a 90-second version)
• "Tell me about a project you're proud of."
• "What was the hardest technical challenge you faced in a project?"
• "How do you approach learning a new technology?"
• "Tell me about a time you asked for help."
• "Why do you want to work here?"
• "Where do you see yourself in 2 years?"

Day 14: Full Mock Interview

• Do a timed session: 35 min DSA problem + 10 min behavioral questions
• Use Pramp.com or ask a friend to interview you

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Week 3 (If You Have It) — Polish

• Revisit every problem you got wrong. Understand why it failed, not just the fix.
• Add 5–10 more medium problems from your weak areas
• Practice explaining your thought process out loud (use a mirror or record yourself)
• Research each company you're interviewing with: product, tech stack, recent news

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Entry-Level Cheat Sheet

Data Structures — Know These Cold

Structure	Key operations	Time complexity
Array	Access, search, insert/delete at end	O(1), O(n), O(1) amortized
Hash Map	Get, set, delete	O(1) average
Stack	Push, pop, peek	O(1)
Queue	Enqueue, dequeue	O(1)
Linked List	Traversal, insert/delete with pointer	O(n), O(1)
Binary Tree	DFS traversal	O(n)

Algorithms — Know These Patterns

Pattern	Signal to use it	Example
Two Pointers	Sorted array + find pair	Two Sum (sorted), 3Sum
Sliding Window	Contiguous subarray/substring	Longest substring without repeats
Fast/Slow Pointer	Linked list cycle, middle	Floyd's cycle detection
BFS	Shortest path, level order	Number of levels in tree
DFS	Explore all paths, connected components	Number of Islands
Hash Map	O(1) lookup, counting frequency	Two Sum (unsorted), anagram

Complexity — Know These by Heart

Your code	Time	Space
Single loop	O(n)	O(1)
Nested loops	O(n²)	O(1)
Loop + hash map	O(n)	O(n)
Binary search	O(log n)	O(1)
Recursion on tree (balanced)	O(n)	O(h) where h = height
Sorting	O(n log n)	O(1) to O(n)

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During the Interview: The 5-Step Process

1. Repeat the problem in your own words before touching code
2. Ask clarifying questions: input size, edge cases (empty input? negatives? duplicates?)
3. Talk through a brute force approach first, then optimize
4. Code while narrating — interviewers need to hear your thinking
5. Test with examples — trace through a simple input before submitting

Questions to always ask before coding

• "What's the expected input size?"
• "Can the array be empty?"
• "Are there duplicate values?"
• "Should I handle null inputs?"
• "Is the array sorted?"

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Common Mistakes to Avoid

❌ Diving into code without thinking — spend 5 minutes planning first ❌ Going silent — narrate your thought process even when you're stuck ❌ Giving up — say "I'm not sure of the optimal approach, can I start with brute force and optimize?" ❌ Forgetting to test — always trace through at least one example ❌ Over-optimizing early — get a working solution first, then discuss complexity ❌ Neglecting behavioral — entry-level behavioral questions are often decisive when two candidates are equal

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Green Flags You're Doing Well

✅ You asked good clarifying questions ✅ You explained your approach before writing any code ✅ You caught a bug yourself while testing ✅ You responded positively to a hint or correction ✅ You made the interviewer feel like a conversation partner, not a judge

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Resume Tips for Entry Level

• Lead with projects if you don't have much experience — put a Projects section above Experience
• Quantify impact: "Built a REST API that handles X requests/day" not just "Built a REST API"
• Include tech stack explicitly: "React, Node.js, PostgreSQL, AWS"
• 1 page maximum — no exceptions
• GitHub link is more valuable than listing "proficient in Java" — show don't tell
• For bootcamp grads: include your final project prominently, be honest about the program duration