A non-transitory computer-readable recording medium having stored therein a program for causing a computer to execute a process is provided. The process includes calculating and outputting difficulty degrees on an index basis when a change instruction to change an arrangement of parts is received with respect to parts and wirings on a substrate in a design diagram, the difficulty degrees being related to the wiring between the parts after the change according to the change instruction; and calculating and outputting difficulty degrees on an index basis when a change instruction to change the wiring between the parts is received, the difficulty degrees being related to the wiring between the parts after the change according to the change instruction.