/* 
 * Example of the while statement
 * 
 * sums a series of numbers, 0 to terminate  
 *
 */ 

#include <stdio.h> 

int main(void)
{
    double x, sum; 

    printf("This program sums a series of numbers.\n"); 
    printf("Enter numbers (0 to terminate):"); 
   
    sum = 0.0; 

    scanf("%lf",&x); 

    while ( x != 0.0 ){
        sum += x; 
        scanf("%lf",&x); 
    }  



    printf("The sum is %.4f",sum); 

    return 0; 
} 

// note that there are two identical calls of scanf, which is
// often hard to avoid when using the while loop