Bridges (Hashi) Puzzles

About Bridges / Hashi Puzzles

Bridges, also known as Hashi or Hashiwokakero, is a logic puzzle that originated in Japan. The name "Hashiwokakero" translates to "build bridges" in Japanese, and that’s exactly the goal of the game. The puzzle is played on a rectangular grid containing islands (circles with numbers) and the player must connect all the islands by drawing a series of bridges between them, following specific rules.

Basic Rules / How to Play

• Islands and Numbers: Each circle (island) contains a number from 1 to 8. This number indicates how many bridges must connect to that island.
• Bridge Limits: Bridges must connect two islands in a straight horizontal or vertical line. Diagonal bridges are not allowed.
• Bridge Count: Up to two bridges can exist between any pair of islands.
• No Crossing: Bridges cannot cross other bridges or pass through other islands.
• Connected Network: At the end of the puzzle, all islands must form one connected network, meaning you can travel from any island to any other island by following the bridges.

Solving Tips and Techniques:

Solving a Bridges puzzle requires logical deduction and careful planning. Here are some common techniques:

• Start with High Numbers: Focus on islands with higher numbers like 8, 7, or 6 first. They need the most bridges and often have fewer choices for where those bridges can go.
• Islands with Maximum Bridges: An island with the number 8 must have two bridges going in four different directions.
• Look for Islands with Only One Possible Connection: If an island’s number matches the number of nearby islands, it must connect to all of them. For example, if an island has the number 2 and only two neighboring islands, it must connect to both.
• Plan Ahead: Be careful not to block islands from making the connections they need. Think ahead to avoid getting stuck.
• Mark Completed Islands:Once an island has the right number of bridges, mark it as finished so you don’t accidentally add more.
• Fill in the Gaps: If an island still needs more bridges and only has one possible direction left to connect, go ahead and draw those bridges.
• Don’t Overdo Bridges: Make sure no island gets more bridges than its number allows. For example, an island with the number 3 can’t have 4 bridges.
• Keep All Islands Connected: As you build bridges, check that no group of islands becomes cut off from the rest. If they do, you’ve made a mistake.
• Avoid Crossing Bridges: Bridges should never cross each other or go through other islands. This is a common mistake when starting out.
• Use Pencil Marks: Draw small dots or dashes to show possible bridge connections. This helps you keep track of options and avoid errors.