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Computer Science Introduction to Algorithms Algorithms in Code Binary Search in Code

Simohamed ALAOUI
Simohamed ALAOUI
3,580 Points

🤔Im still confused about this part 👉 last = len(list)- 1.

If we deduct 1, we get the 3rd position which is the number 4 (i was thinking why we don't add 1 instead of deducting 1. Please Help!

1 Answer

Steven Parker
Steven Parker
217,602 Points

Since index values begin at 0 instead of 1, the highest possible index (and the index of the last item) is one less than the number of items in the list.