Using Z3 to minimize makespan in scheduling problems -


i trying model job shop scheduling problems using z3. let's have set of tasks each of may have other task dependencies. wish minimize time of scheduling last tasks i.e. makespan.

since there can more 1 job has dependencies on other jobs no forward dependencies (i.e. no job depends on one), simple minimize operation in z3 may not suffice. , z3 doesn't admit max function on list.

hence solve this, considering adding fake job depends on such jobs , minimizing time of scheduling job. wonder if approach scalable need add constraints many jobs.

is approach or there other more elegant means?

you can define max using chain of ite calls yourself; assuming know how many jobs there are. see here: use z3 , smt-lib maximum of 2 values


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