Code bloat

Although tht precise size of the programs is not fixed, a maximum size must be, since if no maximum is specified, programs may grow almost without limit (code bloat), as they fill up with inefficient, replicated or irrelevant code. 

Luke, S. (2000). Issues in Scaling Genetic Programming Breeding Strategies, Tree Generation, and Code Bloat, PhD Dissertation, Department of Computer Science, University of Maryland, College Park, Maryland. 

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