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Unformatted text preview: + 1, postcondition: ( z-1)( z + 1) = 0 z := z + 2, postcondition: z 2 + 5 z =-6 2. (6 marks) Prove or disprove that: ( | false | ) x := 2 x ( | false | ) Justify your answer. 3. (7 marks) Consider the skip command which has the eect of not changing any of the assigned values of any of the program variables. Postulate an axiom for the skip statement similar in form to the assignment axiom and reason why your axiom holds over all appropriate triples....
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This note was uploaded on 01/19/2010 for the course CS 246 taught by Professor Wormer during the Spring '08 term at Waterloo.
- Spring '08
- Computer Science