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 (GCC 9.2.1) (judge verdict: Accepted)

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

/*
	入力例：
	3
	1 1 3
*/

int main(){
	long L=0;
	long R=0;
	long d=0;
	long p,e,z;
	long iResult=0;
	scanf("%ld %ld %ld", &L,&R,&d);
	long iCnt;
	iCnt=0;
	for(long i=L;i<=R;i++){
		if (i%d==0){
			iCnt++;
		}
	}
	printf("%ld\n",iCnt);
	return 0;
}