An Challenging Interview question with a difference

The following program is provided:

//Program tested on Microsoft Visual Studio 2008 - Zahid Ghadialy
#include<iostream>

using namespace std;

//This class can be designed as you wish
class SR
{
public:
SR(int i) {}
};

int main()
{
int sum = 0;
for (int i = 1; i < 100; i++)
{
  SR ii(i);
  while (i--)
    sum += i;
}
cout<<"Expected value of sum = 161700" << endl;
cout<<"Returned value of sum = " << sum << endl;

return 0;
}

As already mentioned above, the expected output of 161700 is provided. The class 'SR' could be written as one wishes. How to do write the class 'SR' to get the desired output?

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Give it a try before looking at the solution.

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The modified program with the correct 'SR' class as follows:

//Program tested on Microsoft Visual Studio 2008 - Zahid Ghadialy
#include<iostream>

using namespace std;

//This class can be designed as you wish
class SR
{
public:
 SR(int& i):ref(i)
 {
   var = i;
 }
 ~SR()
 {
   ref = var;
 }
private:
 int var;
 int &ref;
};

int main()
{
 int sum = 0;
 for (int i = 1; i < 100; i++)
 {
   SR ii(i);
   while (i--)
     sum += i;
 }
 cout<<"Expected value of sum = 161700" << endl;
 cout<<"Returned value of sum = " << sum << endl;

 return 0;
}

Source: Modified from here. Another similar question is available here.