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)

// --------------
// Tejas Pandey  |
// 11 - 07 - 20  |
// AIsing ABC    |
// --------------

#include <bits/stdc++.h>
using namespace std;
     
#define mod 1000000007
#define vi vector<int>
typedef long long int ll;
     
int main (void){
  //freopen("in.txt","r",stdin);
  //freopen("out.txt","w",stdout);
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  ll l,r,d;
  cin >> l >> r >> d;
  ll ans = r/d - l/d + (!(l%d));
  cout << ans << "\n";
  return 0;
}