Should I Memorize LeetCode Solutions? (The Nuanced Answer)

"Should I memorize LeetCode solutions?"

Junior engineers ask if it is "cheating." Senior engineers ask what to memorize.

If you try to memorize 2,000+ problems, you will fail. If you refuse to memorize anything and try to derive Dijkstra's algorithm from scratch during a 45-minute interview, you will also fail.

The secret isn't rejecting memorization—it's weaponizing it.

The answer depends on what you mean by "memorize" and what you are trying to achieve. Let us break it down.

The Memorization Spectrum

"Memorization" is not binary. There is a spectrum from rote memorization to deep pattern internalization:

What You Should NOT Memorize

Exact Problem Solutions

Memorizing the exact code for "Longest Substring Without Repeating Characters" is wasteful. There are thousands of problems. You cannot memorize them all, and the interview probably will not have that exact problem anyway.

Problem-Specific Tricks

Some solutions have clever tricks that only work for that specific problem. Memorizing these does not help elsewhere. Example: the XOR trick for "Single Number" is neat but rarely applicable.

Exact Variable Names or Formatting

Do not waste brain space on whether the variable was called "left" or "l" or "start." Focus on the algorithm, not the cosmetics.

What You SHOULD Memorize

Pattern Templates

The general structure of each pattern is worth memorizing. These are not exact solutions to specific problems. They are reusable skeletons that apply to entire categories of problems. Learning them once gives you a starting point for dozens, sometimes hundreds, of variations.

Sliding Window

Used for problems involving contiguous subarrays and substrings, especially when looking for a maximum/minimum length or sum.

left = 0
for right in range(len(arr)):
    # Add arr[right] to window state
    
    while window_is_invalid:
        # Remove arr[left] from window state
        left += 1
    
    # Update result (e.g., max_len = max(max_len, right - left + 1))

Two Pointers (Opposite Ends)

Used for problems on sorted arrays where you need to find a pair that meets a certain condition (e.g., two numbers that sum to a target).

left, right = 0, len(arr) - 1
while left < right:
    current_sum = arr[left] + arr[right]
    if current_sum == target:
        return [left, right]
    elif current_sum < target:
        left += 1  # Need a larger sum
    else:
        right -= 1  # Need a smaller sum

BFS (Shortest Path / Level Order)

The go-to for any "shortest path" on an unweighted graph or "level order traversal" on a tree. The queue is the heart of BFS.

from collections import deque

queue = deque([start_node])
visited = {start_node}
level = 0

while queue:
    for _ in range(len(queue)):  # Process current level
        node = queue.popleft()
        # Process node (e.g., check if it's the target)
        
        for neighbor in get_neighbors(node):
            if neighbor not in visited:
                visited.add(neighbor)
                queue.append(neighbor)
    level += 1  # Move to next level

When you have these skeletons internalized, you do not start from scratch. You start from a working framework and adapt it. This is the core of efficient problem-solving under pressure.

Pattern Recognition Signals

Know when to apply each pattern:

Time/Space Complexity

Know the complexity of common operations and patterns:

• Hash map lookup: O(1)
• Sorting: O(n log n)
• Binary search: O(log n)
• Two Pointers on sorted array: O(n)
• BFS/DFS: O(V + E)

Common Data Structure Operations

How to use heaps, deques, sets, and maps in your language. These are foundational and appear constantly.

The Right Way to "Memorize"

The goal is not rote memorization. The goal is internalization through repeated practice. This is the same difference as memorizing "How to Drive" from a book vs. actually driving every day. For more on the science of this, check out How to Remember LeetCode Patterns. Here is the breakdown:

The Internalization Process

True internalization is not about raw repetition. It is about building procedural memory—the same type of memory that lets you ride a bike or type without looking at the keyboard. Procedural memory is formed through active practice, not passive review.

1. Learn the pattern once, deeply. Understand why it works, not just how. What problem does it solve? What are the constraints? What is the intuition behind the key insight?
2. Solve 5-10 problems using the pattern. Each problem should feel like a variation of the same core idea. If you cannot see the connection, you have not yet internalized the pattern.
3. The "1-3-7-30" Protocol. Do not just "wait a few days." Follow a strict schedule to beat the forgetting curve:
   • Day 1: First successful solve (with help if needed).
   • Day 3: Re-solve from blank slate. If you fail, restart the cycle.
   • Day 7: Re-solve again. This is the "consolidation" test.
   • Day 30: Final confirmation. If you pass, the pattern is internalized.
   For a deep dive on this, read our guide on Spaced Repetition for Coding Interviews.
4. Teach it to someone else. Explaining a pattern exposes gaps in understanding and deepens retention. This is the "Feynman Technique" in action: if you cannot explain it simply, you do not understand it well enough.

Example: Internalizing Two Pointers in One Week

Here is a concrete example of how to apply this process:

After one month, if you can still solve a Two Pointer problem in under 15 minutes without hesitation, you have achieved internalization. The pattern is now a tool you own, not a solution you memorized.

The Bottom Line

Yes, you should memorize—but not exact solutions. Memorize:

• Pattern templates (the skeleton of each approach)
• Pattern recognition signals (when to use what)
• Complexity analysis (time and space trade-offs)
• Data structure operations (your language's toolset)

Do not memorize:

• Exact problem solutions
• Problem-specific tricks
• Code formatting details

How TerminalTales Builds Internalization

TerminalTales is designed for pattern internalization, not rote memorization:

• Pattern-centric chapters — Each chapter teaches one pattern deeply with multiple variations.
• Spaced repetition — Patterns are automatically reviewed at optimal intervals.
• Active recall — You implement solutions from scratch, not just read them.
• Story context — Patterns are connected to memorable scenarios, enhancing retention.

Do not ask "should I memorize?" Ask "have I internalized the patterns?" The answer to that question determines your interview success.