Problem:
Score : 100 points

Problem Statement

How many multiples of d are there among the integers between L and R (inclusive)?

Constraints

All values in input are integers.

1 \leq L \leq R \leq 100

1 \leq d \leq 100

Input

Input is given from Standard Input in the following format:

L R d

Output

Print the number of multiples of d among the integers between L and R (inclusive).

Sample Input 1

5 10 2

Sample Output 1

3

Among the integers between 5 and 10, there are three multiples of 2: 6, 8, and 10.

Sample Input 2

6 20 7

Sample Output 2

2

Among the integers between 6 and 20, there are two multiples of 7: 7 and 14.

Sample Input 3

1 100 1

Sample Output 3

100

Solution in C (Clang 10.0.0) (judge verdict: Wrong Answer)

#include <stdio.h>

int main(){
  int x,y,z,N,count = 0;
  scanf("%d", &N);

  for(int i = 1; i < N+1; i++){
 	 for(x = 1; x < 50; x++){
 	   for(y = 1; y < 50; y++){
 	     for(z = 1; z < 50; z++){
    	    if((x*x + y*y + z*z + x*y + y*z + x*z == i))
              count++;
         }
       }
     }
  	printf("%d\n", count);
    count = 0;
  }
  return 0;
}