results in the table illustrate, the proposed exact approach outperforms the competing algorithms, successfully solving to optimality each instance in at most 1 second (this maximum CPU time is reached in instance 55-3) with an average of 0.2 seconds. Also, the number of subproblems explored in Step 2 and the number of models $CRIT_2(c)$ solved are very limited. Notice that the tests in [@CaCarLoWo16] and in [@FiLjMoSi18] were carried out on different but comparable machines in terms of hardware specifications.

[|rr||\*[1]{}[c|]{}\*[1]{}[c|]{}\*[1]{}[c|]{}\*[1]{}[c|]{}]{}

& & Optimal & CPU & \# Subprob. & \# $CRIT_2(\cdot)$\
*n* & *INS* & Value & Time & in Step 2 & solved\

35 & 1 & 279 & 0.11 & 3 & 5\
& 2 & 469 & 0.36 & 0 & 2\
& 3 & 448 & 0.43 & 2 & 4\
& 4 & 370 & 0.15 & 2 & 4\
& 5 & 467 & 0.14 & 2 & 4\
& 6 & 268 & 0.05 & 0 & 0\
& 7 & 207 & 0.04 & 0 & 0\
& 8 & 41 & 0.03 & 0 & 0\
& 9 & 80 & 0.03 & 0 & 0\
& 10 & 31 