Question

Given a queue of integers, write an algorithm and the program in c++ that, using only the queue ADT, calculates and prints the sum and the average of the integers in the queue without changing the contents of the queue.

Answer 1

// C++ program to calculate sum and average of the integers in the queue without changing the contents of the queue.

#include <iostream>

#include <queue>

using namespace std;

int main() {

       queue<int> q; // create an empty queue of integers

       int sum = 0;

       // push elements 1 to 10 in q such that 1 is at the front and 10 is at the end

       for(int i=1;i<=10;i++)

             q.push(i);

       // create another temporary queue which is empty initially

       queue<int> temp;

       // loop that removes the element from q and inserts into the temporary queue and add the element to the sum

       // queue removes the element from front and inserts the element at the back

       // so temp will contain the element in the same order as present in q

       while(!q.empty())

       {

             int num = q.front(); // get the front element of the queue

             q.pop(); // remove the front element from the queue

             sum += num; // add the num to sum

             temp.push(num); // push the num to temp queue

       }

       // loop that continues till temp is not empty

       // q will contain the element in the same order as it was present initially

       while(!temp.empty())

       {

             q.push(temp.front()); // push the front element of temp to q

             temp.pop(); // remove the front element from temp

       }

       // print the sum and average

       cout<<"Sum : "<<sum<<endl;

       cout<<"Average : "<<((double)sum)/q.size()<<endl;

       return 0;

}

//end of program

Output: