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dreamcode
dreamcode
Lesson
Practice · Hash map patterns
  1. Predict
  2. Arrange
  3. Fill in
+20 XP on finish
PREDICT · READ BEFORE YOU WRITE

What does this program print?

Trace the program the way the computer would, then make your call before running anything.

const counts = {};
for (const ch of "banana") counts[ch] = (counts[ch] || 0) + 1;
console.log(counts);