In this letter, an e ective technique is proposed for improving the computational e ciency of the contraction-type LP test algorithm, which is an algorithm for ÿnding all solutions of piecewise-linear resistive circuits. Using the proposed technique, all solutions of a large-scale problem, where the number of variables is 100 and the number of linear regions is 10 100 , could be found in less than 10 min using a 360 MHz computer. , if there is no connected region in the xm-direction, then it is not necessary to join regions [for example, see the right-hand block B 2 in Figure 1(c)]. However, we do not consider such a case because in that case, Technique 2 described in Reference [1] can be applied with minor and trivial modiÿcations. Note that we cannot start the simplex method from point B because B is not a vertex of the feasible region in region 2+3.