2 What would be the value of queues Q1 and Q2 and stack S af

2. What would be the value of queues Q1 and Q2, and stack S after the following algorithm segment:

1 S = createStack

2 Q1 = createQueue

3 Q2 = createQueue

4 enqueue (Q1, 5)

5 enqueue (Q1, 6)

6 enqueue (Q1, 9)

7 enqueue (Q1, 0)

8 enqueue (Q1, 7)

9 enqueue (Q1, 5)

10 enqueue (Q1, 0)

11 enqueue (Q1, 2)

12 enqueue (Q1, 6)

13 loop (not emptyQueue (Q1))

1 dequeue (Q1, x)

2 if (x == 0)

1 z=0

2 loop (not emptyStack (S))

1 popStack (S, y)

2 z=z+y

3 end loop

4 enqueue (Q2, z)

3 else
1 pushStack (S, x)

4 end if

14 end loop

This is a C data structure question. Please use C language, thank you very much!

Please find below the execution results of this above algorithm :

After step 12 : Q1 = {5,6,9,0,7,5,0,2,6} // after step 12

dequeue Q1: x = 5 after dequeue Q1 ={6,9,0,7,5,0,2,6}
x != 0 ; thus push x into Stack S, thus S = {5}

dequeue Q1: x = 6 after dequeue Q1 ={9,0,7,5,0,2,6}
x != 0 ; thus push x into Stack S, thus S = {5,6}

dequeue Q1: x = 9 after dequeue Q1 ={0,7,5,0,2,6}
x != 0 ; thus push x into Stack S, thus S = {5,6,9}

dequeue Q1:    x = 0         after dequeue Q1 ={7,5,0,2,6}
       x == 0 ;thus let z = 0;
           pop stack S; y = 9 after pop S = {5,6}
           z = z + y = 0 + 9 = 9

           pop stack S; y = 6 after pop S = {5}
           z = 9 + 6 = 15

           pop stack S; y = 5 after pop S = {}
           z = 15 + 5 = 20

           stack S is empty; thus enqueue z into Q2; thus Q2 = {20}

dequeue Q1: x = 7 after dequeue Q1 ={5,0,2,6}
x != 0 ; thus push x into Stack S, thus S = {7}

dequeue Q1: x = 5 after dequeue Q1 ={0,2,6}
x != 0 ; thus push x into Stack S, thus S = {7,5}

dequeue Q1:    x = 0         after dequeue Q1 ={2,6}
       x == 0 ;thus let z = 0;
           pop stack S; y = 5 after pop S = {7}
           z = z + y = 0 + 5 = 5

           pop stack S; y = 7 after pop S = {}
           z = 5 + 7 = 12

           stack S is empty; thus enqueue z into Q2; thus Q2 = {20,12}

dequeue Q1: x = 2 after dequeue Q1 ={6}
x != 0 ; thus push x into Stack S, thus S = {2}

dequeue Q1: x = 6 after dequeue Q1 ={}
x != 0 ; thus push x into Stack S, thus S = {2,6}

Q1 is empty; thus exits loop.

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From the above execution sequence we can find that the values in Q1, Q2, and S are :

Q1 = { } (empty)

Q2 = { 20, 12 }

S = { 2, 6 }