 The GenProg Evolutionary Program Repair software repaired 55 out of 105 bugs for approximately $8 each in one test.Coevolution adopts a "predator and prey" metaphor in which a suite of programs and a suite of unit tests evolve together and influence each other.Search-based software engineering has been applied to software testing, including automatic generation of test cases (test data), test case minimization and test case prioritization.