One aspect of the present disclosure relates to a conversion device including an acquisition unit configured to acquire a first bit string having a first bit length L1; a conversion unit configured to convert, in accordance with conversion information that associates respective bit strings each having the first bit length L1 with bit strings each having a second bit length L2 uniquely assigned to the respective bit strings, the first bit string into a second bit string having the second bit length L2. The conversion information is created by searching for a clique that includes 2.sup.L1 or more nodes, from a graph including nodes and an edge representing the bit strings each having the second bit length L2 that satisfy a predetermined constraint condition.

One aspect of the present disclosure relates to a conversion device including an acquisition unit configured to acquire a first bit string having a first bit length L1; a conversion unit configured to convert, in accordance with conversion information that associates respective bit strings each having the first bit length L1 with bit strings each having a second bit length L2 uniquely assigned to the respective bit strings, the first bit string into a second bit string having the second bit length L2. The conversion information is created by searching for a clique that includes 2.sup.L1 or more nodes, from a graph including nodes and an edge representing the bit strings each having the second bit length L2 that satisfy a predetermined constraint condition.