#include <stdio.h>
void main(void)
{
	/* The simple program that finds the sum of  
	   all numbers read up to a negative number using simple while 
		structure */


	float num, sum;

	/* initialize the control variable and ohters   */

	sum = 0;
	
	printf("please type the first number \t:");
        scanf("%f", &num);


	/* test for loop continuation using control variable  */

	while (num >= 0)
	{
		sum += num;

		/* Now update the control variable */

		printf("please type the next number \t:");
        	scanf("%f", &num);


	}

	
	printf("sum = %0.2f \n", sum);

}