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// remember what made it click

Remember the insight, not just the answer.

Save the one thing that made a LeetCode problem click. Your notes stay on your device, ready whenever you need to remember why the solution worked.

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local-first·no account·no AI-written notes
minimum-window-substring.md
#76

Minimum Window Substring

hard
Sliding Window
Recall 67%hint

Expand right until the window is valid, then shrink from left while it stays valid. Track how many required characters are still missing instead of recounting the map every step.

Recall 67%·6 reviews·Last reviewed 3 days ago
1 forgot · 2 shaky · 3 got it
#1easy
Two Sum
HashingRecall 94%
#124hard
Binary Tree Maximum Path Sum
TreesRecall 38%

Your notes, after the solve.

01Solve

Finish the problem on LeetCode.

02Write

Save what made it click, what tripped you up, and what you want to remember.

03Recall

Come back later. Try to reconstruct the approach before revealing your notes.

/*

You solved it.

Write down why.

CodeClick saves your insight, mistakes, and gotchas instead of generating another explanation for you. Your notes are worth keeping because you wrote them.

*/
personal_notesWrite your own insight and gotchas.
study_modeHide the answer until you're ready to reveal it.
focus_viewOne problem at a time, nothing else on screen.
local_firstStored locally in your browser. No account required.

Try to remember → reveal your notes.

#76

Minimum Window Substring

hard
recall the approach before revealingreveal ↓
Recall 67%·6 reviews·Last reviewed 3 days ago
1 forgot · 2 shaky · 3 got it
#76

Minimum Window Substring

hard
Sliding Window
Recall 67%hint
// what made it click

Expand right until the window is valid, then shrink from left while it stays valid. Track how many required characters are still missing instead of recounting the map every step.

// complexityO(n) time · O(k) space
// notes / gotchas
Duplicates in t count. Record the answer before shrinking, not after.
Recall 67%·6 reviews·Last reviewed 3 days ago
1 forgot · 2 shaky · 3 got it
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Solve it once. Remember why.

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