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 <bits/stdc++.h>
#define dbg(x) cout << #x << ": " << (x) << '\n'
#define ff first
#define ss second
#define ll long long
#define rep(i, n) for (int i = 0; i < n; i++)
using namespace std;

int main() {
   ios::sync_with_stdio(false);   cin.tie(NULL);   cout.tie(NULL);

   int l, r, d;
   cin >> l >> r >> d;
   cout << (r / d) - (l / d) + bool(!(l % d)) << '\n';


   return 0;
}