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

process p
const v
var ready : array [0..v-1] of boolean;   {init. true}
    i     : 0..v-1

par j : 0..v-1

begin
   ready[j]           -> send rqst(j) to q;
                         ready[j] := false

[] rcv rply(i) from q -> ready[i] := true

[] rcv rqst(i) from q -> send rply(i) to q;           
end

Another solution:

process p
const v
var ready : array [0..v-1] of boolean,   {init. true}
    i, j  : 0..v-1

begin
   ready[j]           -> send rqst(j) to q;
                         ready[j] := false;
                         j := j +v 1

[] rcv rply(i) from q -> ready[i] := true

[] rcv rqst(i) from q -> send rply(i) to q;   

[]~ready[j]           -> j := j +v 1

end

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2. 

process p[i : 0..m-1]
const m,n
var ready : boolean;   {init. true}

begin
   ready           -> send rqst to d;
                      ready := false

[] rcv rply from d -> ready := true
         
end

process d
const m,n
var x : 0..m-1,  
    y : 0..n-1  {init. 0}

par i : 0..m-1;
    j : 0..n-1

begin
   rcv rqst from p[i] -> send rqst(i) to q[y];
                         y := y +n 1

[] rcv rply(x) from q[j] -> send rply to p[x]
         
end

process q[i : 0..n-1]
const m,n
var x: 0..m-1

begin

  rcv rqst(x) from d -> send rply(x) to d
         
end

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