Walkthrough ‐ Classic III.C: XOR Frugality

Learning Objectives

• The player is challenged construct a logical XOR without the use of inversion gates.
• Similar to the preceding level, this level also touches on the topic of universality in logic gates; many of the components in The Qubit Factory are not strictly necessary as an equivalent result could be produced using combinations of other components.

Solution

1. Bits from input B are split into two different channels, via a control with a combiner gate, depending on the bits from input A.
2. Bits in the lower channel are inverted through use of a re-zero and a creation component.

Level File (copy then paste into Qubit Factory)

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