Figure 4.

(Left) Quantum circuit computing the match between two 16 elements long input sequence of 6-bit values A and B, encoded on qubits $a_i$ and $b_i$, respectively. The QBArt unitary prepares the initial state. The 6 CX gates compute the XOR between bits of sequences element. The following 5 nested Toffoli gates set the output qubit $m_0$ to state $\left|1\right.〉$ if both 6-bit input pairs match. The intermediate XOR output result is also measured on qubits $p_i$. (Right) Results obtained by the DNA sequence matching executed on Quantinuum H1-1 QPU. The algorithm correctly detects the differences between the 6 codons in positions 5 to 10, marked in red. (a) 6-bit XOR$(\overrightarrow{A},\overrightarrow{B})$ output sequence and (b) measured match-bit, both follow the ground-truth.