JavaScript practice arena
Twelve problems. One ordered path.
Start with input handling, then progress through stacks, search, and sliding windows. Run every solution in your browser, submit against deterministic checks, and return to your next unfinished step.
Start step 1 of 1212-problem path · JavaScript
Build from input handling to sliding windows.
Each problem runs in browser-based JavaScript. Signed-in attempts are saved to your account.
12 problems
Language foundations
Parse input, choose a branch, and control a loop.
Data and iteration
Traverse arrays and strings, then combine simple rules.
Collections and structure
Track membership, preserve order, and use a stack.
Search patterns
Count occurrences, narrow a range, and maintain a window.