The Hamiltonian Circuit vs Sumaddle

Find a path that visits every square in the grid, avoiding walls and never crossing itself, to create one continuous circuit. To get the hang of things, start with one of the simple 4x4 grids. Plot your moves carefully. Try to think ahead; not just by one square, but by four or five. If you think you've made a mistake, trace back over your line. It will disappear. If you really get stuck, press Hints. Any mistakes will turn red, then disappear. But if you're on the right path, we'll add a line. There's only one solution for every puzzle. When you find it, you'll know. Puzzles start with 4x4 grids and go all the way to 20x20. The bigger puzzles are very challenging and can take hours to solve. If you have to quit in the middle of one, don't worry: your progress is automatically saved. Many find working on these circuits meditative; others reach for the ibuprofen. But no matter which camp you find yourself in, know you're exercising your abstract thinking skills and challenging your brain in ways that actually matter. Inspired by a puzzle created by Irish mathematician William Rowan Hamilton in 1856, these circuits start off easy and get hard. Really hard. Good luck! Terms of use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

This type of logical puzzle was first seen in the Japan Puzzle Championship 2006 and is sometimes known as Doppelblock, or Smashed Sums. When played with pencil and paper, these puzzles can be hard work to solve. Sumaddle changes that by transforming the puzzles into interactive brain teasers that unfold before your eyes. Each puzzle has a unique solution. Finding the solution involves fitting the number combinations to the clues. The app makes it easy to view the possible combinations, you don’t need to do any sums in your head. Instead, you are able to focus on using logic to narrow down the combinations and find a fitting arrangement. The puzzles come in a range of sizes and difficulties, to suit all levels of skill and puzzling purposes. Choose a small puzzle to idle away a minute or two while waiting in a queue, or a big puzzle to give your brain some exercise during a coffee break! Some reasons why you will enjoy playing Sumaddle: • more than 150 puzzles are included for free • all puzzles can be solved with pure logic, no mental arithmetic required • the sophisticated built-in help can explain the logical reasoning at each step and also fix mistakes if you go wrong • the built-in help is completely free, use it as much as you like • works offline (great for long journeys) • a high standard of accessibility, including comprehensive support for VoiceOver • ad-free play - there are absolutely no ads! IGRS age rating (Indonesia Game Rating System): 3+ Designed and developed in Winterthur, Switzerland