// while loop example 1

#include <iostream>
using namespace std;

int main()
{
	int sum = 0, num = 0;
	bool getMeOuttaHere = false;

	while (sum < 1000 && !getMeOuttaHere)
	{	
		cout << "Enter a number [-1 to exit]: ";
		cin >> num;

		if (num == -1)
		{
			getMeOuttaHere = true;
		}
		else
		{
			sum += num;	
		}
	}

	cout << sum << endl;		
	return 0;
}// end of main