a4 - swap statement with the following syntax x:= y...

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CSE 755, Assignment #4 Due: 17 May ’06. Important Note: The second mid-term will be on Monday, May 19. 1. (3 points). Derive the following using the axioms and rules of inference we have seen: (a) { x = 1 } if ( y = x ) then y := x else y := x { y = 1 } (b) { false } while x > 0 do x := x + 1 { x = 10 } 2. (4 points). Consider the following program: { (x=1) (y=10) } while ( x 6 = 10) do x := x+1; { (x=y) } Derive the above result using the standard axioms and rules we have seen. If the result cannot be derived, explain what the problem is. 3. (3 points). Consider a
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Unformatted text preview: swap statement with the following syntax: x :=: y ; Operationally, the effect of executing this statement is to exchange the values of x and y . Propose an axiom for this statement. Explain your axiom. (You may have to introduce some new notation –similar to the p x e notation we used in the assignment axiom– corresponding to this axiom; if you do that, make sure you explain the meaning of your notation.) 1...
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This homework help was uploaded on 04/10/2008 for the course CSE 755 taught by Professor Neelamsoundarajan during the Winter '05 term at Ohio State.

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