Solution of 11934 - Magic Formula

Problem Description
source: https://uva.onlinejudge.org/external/119/p11934.html

You are given a quadratic function, 
                           f(x) = ax2 + bx + c 
You are also given a divisor d and a limit L. How many of the function values f(0), f(1), . . . , f(L) are divisible by d? 

Input

 Input consists of a number of test cases. Each test case consists of a single line containing the numbers a b c d L (−1000 ≤ a, b, c ≤ 1000, 1 < d < 1000000, 0 ≤ L < 1000). 
Input is terminated by a line containing ‘0 0 0 0 0’ which should not be processed. 


Output 

Print the answer for each test case (the number of function values f(0), f(1), . . . , f(L) divisible by d) on a separate line. 

Sample Input 

0 0 10 5 100 
0 0 10 6 100 
1 2 3 4 5
1 2 3 3 5
0 0 0 0 0 

Sample Output 

101 
0 
0 
4

Solution:

#include<stdio.h>
#include<math.h>

int main()
{
    long int n, a,b,c, d, l, count,x;
    while(scanf("%ld%ld%ld%ld%ld",&a, &b, &c, &d,&l)==5)
    {
        if(a==0 && b==0 && c==0 && d==0 && l==0)
            break;
        count=0;
        for(x=0;x<=l;x++)
        {
            n=(a*x*x) +(b*x)+c;
            if(n%d==0)
                count++;
        }
        printf("%ld\n",count);
    }
    return 0;
}