/*File:  SentinelLoop02.cpp
This C++ program illustrates the use of a do-while loop to 
implement a sentinel loop.  Typical screen output from this
program follows: 

Enter a grade or -1 to quit.
20
Enter a grade or -1 to quit.
40
Enter a grade or -1 to quit.
60
Enter a grade or -1 to quit.
-1
Average = 40
**********************************************************/

#include <iostream>
using namespace std;

class SentinelLoop02{ 
  public:
  static void classMain(){
    SentinelLoop02* ptrToObject = new SentinelLoop02();
    ptrToObject -> doSomething();
  }//End classMain function
  //-----------------------------------------------------//

  //An instance function of the SentinelLoop02 class
  void doSomething(){
    int count = -1;
    double sum = 0;
    double temp = 0;

    do{
      count = count + 1;
      sum = sum + temp;
      cout << "Enter a grade or -1 to quit." << endl;
      cin >> temp;
    }while(temp != -1.0);

    if(count > 0){
      cout << "Average = " << sum/count << endl;
    }//end if

  }//end doSomething function
};//End SentinelLoop02 class
//-------------------------------------------------------//

int main(){
  SentinelLoop02::classMain();
  return 0;
}//end main

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