One Stroke Drawing Puzzle
OneStrokeV asks you to cover every line in a figure without lifting your finger and without retracing. It is the Euler path problem as a puzzle, with fifty hand-checked levels across four difficulty tiers.
How to play OneStrokeV
- Tap a green node to choose your starting point.
- Tap a connected node to draw along the line between them.
- Cover every line exactly once. You may pass through a node more than once.
- If you strand yourself with lines left over, reset and try a different start or route.
- Clear the level to move on. There are fifty across four tiers.
How scoring works
A level is scored on completion, with fewer resets scoring higher. Every one of the fifty puzzles is guaranteed solvable, so a failed attempt is always a routing mistake rather than an impossible figure. The four tiers increase both the number of lines and the number of dead ends that look like progress.
Three ways to score better
- Start at a node with an odd number of lines if there is one. That is where a valid single stroke has to begin.
- Count the odd nodes before you start. Zero or exactly two means a single stroke exists.
- Leave the long outer loops for last. They are usually the only lines that can safely be traversed at the end.
Common questions
Is every puzzle actually solvable?
Yes, all fifty are guaranteed solvable. If you get stuck, the route was wrong rather than the figure.
What is the trick to starting correctly?
Look for a node with an odd number of lines attached and begin there. A figure with exactly two such nodes can only be drawn by starting at one and finishing at the other.
Can I go through the same point twice?
Through a node, yes, as often as you like. Along the same line, no — every line must be covered exactly once.
More challenges
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- SequenceVFind the rule behind the run, then give the next term.
- DailyVFive short challenges. Same set for everyone, every day.
- BrainBattleVA five-round tournament across reaction, observation, logic, knowledge and accuracy.
- ReactionVWait for green, then tap. Measures your reflexes to the millisecond.
OneStrokeV is one of 25 challenges in ChallengeV, part of Apps by V. It runs entirely in your browser, works offline once loaded, needs no signup, and keeps your scores on your own device rather than on a server. Everything here is for entertainment — it is not a test or an assessment of any kind.