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Mohamed G. Gouda                                        CS 356
Summer 2006                                             Midterm 2 
Solution
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1. 

process p
const w
var na, ns, i : integer {init. 0}

begin

na + w > ns -> if na = ns -> {send short msg} send data(ns) to q
               [] true    -> {send long msg}  send data(ns) to q
               fi; ns:= ns+1

... (other actions are the same as the ones in the textbook)

end

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2. 

rcvd[s], rcvdtxt[s] := true, t;
do rcvd[exp] -> 
   rcvd[exp], txt[x],       exp,        x  :=
   false,     rcvdtxt[exp], exp + 2n 1, x+1
od

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