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>
using namespace std;
typedef long long ll;
#define In_The_Name_Of_Allah_The_Merciful ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define Alhamdulillah return 0;
#define all(v) v.begin(),v.end()
#define debug(n) cerr << "[" << #n << " = " << n << "]" << endl 

void Suhaib_Sawalha (){

    int n , m , d;
    cin >> n >> m >> d;
    int ans = 0;
    for (int i = 1 ; i <= 100 ; ++i){
        ans += (d * i <= m && d * i >= n);
    }
    cout << ans;
}

int main(){
                                In_The_Name_Of_Allah_The_Merciful   /* بسم الله الرحمن الرحيم  */
#ifndef ONLINE_JUDGE
    freopen("SuhaibSawalha1.txt","r",stdin);
#endif
//int _;for(cin>>_;_;--_,cout<<'\n')
        Suhaib_Sawalha();
                                         Alhamdulillah                    /* الحمد لله */
}