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 N 200050
#define M 200
#define int long long
#define pb push_back
#define x first
#define y second
#define all(v) v.begin(),v.end()
#define coffee prince
#define sz(a) (int)a.size()
#define ll long long
#define SIZE N
#define MOD mod
using namespace std;

signed main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
    int l,r,d;
    cin>>l>>r>>d;
    int ans = r/d;
    if(l)ans -= (l-1)/d;
    cout<<ans;
  	return 0;
}