Coding-decoding

Find the letter rule in three examples, then apply it to a new code.

Move every letter by the same amount.

Find the rule that fits every example.

A?Z?C?

Move each letter forward by one.

Unscored example · no round used

How to play

Compare the three input–output examples, then choose the coded form of the new input. Only the rules named for the level are allowed. Level 1 shifts every letter by the same amount; level 2 alternates two different shifts, starting at the first letter; level 3 reverses the letters, then shifts them all equally. Each shift is 1 to 4 places forward or backward in A–Z, wrapping from Z to A or A to Z. Check all three examples before choosing.

Use touch or a mouse, or Tab to move between controls and Enter or Space to select.

Original letter-rule exercises using the English alphabet. The codes do not need to form words, and vocabulary is not tested.

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