Learn Gridlock
Five habits that turn a jammed lot into a short, clean solve. Start with the red car’s lane: everything else follows from what’s in it.
How to play GridlockA one-minute video walkthrough is on its way.
1. Read the lane first
Before touching anything, name every vehicle between the red car and the exit. Those are the whole puzzle.
The red car only ever moves along its own row, so the only cars that truly matter at the end are the ones sitting in that row between it and the exit. Count them before you move anything. On an Easy puzzle there might be one or two; on a Hard one, three vertical vehicles stacked in a row is common.
Every one of those blockers has to end up entirely above or below the red car’s row. Keep that picture as the goal, and every other move on the lot is just a way of making room for it.
2. Chase the blockers
For each car in the lane, ask which way it can leave and what stands in the way of that. Follow the chain until something can move.
Take one blocker at a time and ask two questions: can it leave the lane going up, going down, or both, and what is in the way of each? A car two cells long needs two free cells above or below the lane to clear it; that space is usually taken by something else.
Then ask the same of whatever is in the way, and so on. The chain ends at a vehicle that can move right now. That is your first move, and the chain tells you the order of the next few. Most puzzles are one or two chains like this, tangled together.
3. Trucks decide
A vertical truck in the lane has to go all the way up or all the way down to clear it. Work out which before anything else.
A truck is three cells long and the lot is six, so a vertical truck crossing the red car’s row can only clear it by going all the way to the top or all the way to the bottom. If the top is blocked by something that can never move, the truck has to go down, and you know which cells to empty for it.
Because trucks are so limited, they set the order of the whole solve. Work out where each truck in the lane must end up first, then plan the cars around it.
4. Back up to go forward
The best move often takes a car away from where it needs to end up, to open a lane for something else first.
The moves that feel like progress (the red car creeping forward, a blocker nudged halfway) are often the ones that lock the lot. A car sitting just past a corridor can stop a truck from getting through, and the fix is to move it back the way it came.
If you are stuck, look for a vehicle that is in a good-looking spot and ask what it is stopping. Moving it away, even toward where it started, is usually the step that opens everything up.
5. One slide, one move
A move is one vehicle slid any distance. Decide where it’s going and take it all the way, and par gets reachable.
Gridlock counts moves the way the solver does: one vehicle slid any distance is one move, no matter how many cells it travels. Nudging the same car twice in a row still counts once, and sliding it straight back to where that run started takes the move back.
Par is the fewest moves the puzzle can be solved in, worked out by trying every possible line of play. Hitting par means every car went exactly where it needed to in one go. Plan a few moves ahead, slide each vehicle to its final spot, and you will hit it more often than you think.
Try them out: play Gridlock. Start on Easy to get a feel for the lanes, then see how close to par you can get on Hard.