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We tried only going forwards. These are some of the routes that get from the start to the end.
Start 3, 3, 1, 3, 2, 2, 4, 4, 2, 1, 4, end
Start 3, 3, 1, 3, 2, 2, 4, 4, 2, 1, 1, 3 end
Start 1, 4, 1, 1, 3, 2, 2, 4, 4, 2, 1, 4, end
Start 1, 4, 1, 1, 3, 2, 2, 4, 4, 2, 1, 1, 3 end
Start 1, 1, 2, 2, 1, 3, 2, 2, 4, 4, 2, 1, 4, end
Start 1, 1, 2, 2, 1, 3, 2, 2, 4, 4, 2, 1, 1, 3 end
We tried all the starting combinations with 1 and 3. We found that no matter what numbers you chose you always land on the square 4/3. Then if you choose 4 then you get stuck at 0/0, so you have to move 3 onto 3/2. If you choose 3 you land on 0/0, so you have to move 2. The middle part of the route is always the same 3, 2, 2, 4, 4, 2, 1.
The quickest way to get to 4/3 is 3, 3, 1 or 3, 1, 3. The quickest way to end is to choose 4 on square 4/1 near the end.
We had different strategies and tried out different ideas
James “With only forwards moves it is impossible to land on the squares 3/1, 2/1, 2/3, 2/4, 1/0, 3/3, 3/0, 0/1”
Chris “I tried getting back to the start from the 2/4 square near the end. It wasn’t possible, I always ended up on the 0/0s. 2/3, 2/2, 2/1 and 3/1 to the left of the end square were dead ends and there is no way of jumping over them.”
Emerald “I didn’t like to land on a square with a zero, because then I didn’t have a choice.” “Going backwards you will always end up on 0/0, no matter which of the inside squares you start on.”