How to Solve a Leap Frog Test

The typical "Leap Frog Test" features six frogs facing each other atop seven stones. The three right-facing frogs sit on the three leftmost rocks, while the three left-facing frogs sit on the three rightmost rocks, leaving an empty rock between the two groups. The goal is to switch the positions of the frogs, so the left-facing frogs are on the left rocks, and the right-facing frogs on the right rocks. However, a frog can only move to an empty rock directly in front of it or two spaces in front of it, leaping another frog to get to the space.

Instructions

1. Start by moving the innermost frog on the left (L1) forward one space. Make the innermost frog on the right (R1) hop L1. Move the second frog on the right (R2) to the rock in front of L1. Have L1 hop R2 and onto the sixth rock from the left.

2. Have the second frog in the left group (L2) leap over R1. Then have the last frog on the left (L3) to move on to the empty rock to its right. Next have R1 jump over L3 and onto the far left rock.

3. Move R2 and R3 forward two rocks each, by having them each leap over the frogs in front of them. You'll need to move R2 first. At this point, the frogs should be in this order: R1, L3, R2, L2, R3, L1, empty rock.

4. Move L1, L2, and L3 forward, in that order. L1 will move to the empty rock. L2 and L3 will each leap over a left-facing frog.

5. Move R2 and R3 into their final places. Click R2 to have it jump one rock forward, and R3 to have it leap over L3 and into its final place.

6. Move L3 forward to the empty rock and complete the test.

References

• Frog Leap Test