Checkpoint: runs count once

Challenge on lesson: Checkpoint: compose under contract

CHALLENGE

Difficulty: intermediate+25 XP

Upgrade the broken compress: sum elements, but each RUN of equal adjacent elements counts once ({2,2,5,5,5,1} → 8). The broken version sums every element (15). Compare each element with its predecessor — one extra condition in the loop body is enough.

Press Submit to check your solution.

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