Weakest preconditions and cumulative subgoal fulfillment
We discuss the use of weakest preconditions with the cumulative subgoal fulfillment (CSF) approach. We use an example of Cohen and Monin for this contrast. We show how the CSF process makes correctness integral with program construction. We show how CSF produces the Cohen/Monin program as well as an additional O(n) O ( n ) solution. We show how CSF yields O ( log n ) solutions.
weakest preconditions subgoals correctness invariant methodology