Figure 5.

Relating 1-MCP_c and 1-MCP_ℓ. (a) The breakpoint graph ; black edges are and and gray edges are . The edge e = {1_t, 6_h} is the only edge in . Since e is not in a cycle component of B, we have θ(e) = 1. (b) The breakpoint graph , where is a completion of and a solution to 1-MCP_c. The adjacency f is in and shown by a gray dashed edge. B' has two cycles, and removing e and f decreases the number of cycles by one.