Bridges: matching the numbers is only half the puzzle

Bridges has joined TAPA GAME's logic puzzles. Each island carries a number showing how many bridges must touch it. You can draw one or two bridges between aligned islands, but lines cannot cross or pass through another island. The final board must also be one connected network.

Count the available neighbors

An island near a corner may have very few legal neighbors. Start there. Because each connection can hold at most two bridges, a high number with only a few neighbors puts strong limits on the possible arrangement.

For example, an island that needs four bridges and has only two possible neighbors needs two bridges to each. Check that the routes are genuinely available before treating that deduction as fixed.

Watch for separate groups

It is possible to satisfy several island numbers while sealing those islands off from the rest of the board. That does not finish the puzzle. Before completing a small group, look for a remaining route that can connect it to another island.

The connection rule matters throughout the solve, not just at the end. A locally neat arrangement can use up every bridge on the islands that would otherwise connect two areas.

Drawing and changing bridges

Tap two islands to connect them. Selecting the same pair again cycles through one bridge, two bridges and no bridges. Keyboard play uses the arrows and Enter; U undoes a move and R retries the level.

There are twenty boards. Give each one a quick survey of sparse corners and crowded junctions before drawing. The numbers tell you what each island needs, while the gaps tell you which connections are possible.