#include<iostream>
using namespace std;

int main()
{
 // Declare variables
 int inputNum, sum=0;

 // Keep looping while inputNum is non-negative
 do
 {
   cout << "Sum is " << sum << endl;

   // Get new input number
   cout << "Enter new number: ";
   cin >> inputNum;

   // Add input to running sum
   sum += inputNum;

 } while(inputNum>=0);

 return 0;
}