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 x first
#define y second
#define pb push_back
#define mk make_pair
#define all(a) a.begin(), a.end()
#define len(a) (int)a.size()

using namespace std;

typedef long long ll;
typedef vector <int> vi;
typedef pair <int, int> pii;

int main(){
	int l, r, d;
	cin >> l >> r >> d;
	
	int cnt = 0;
	for(int i = l; i <= r; i++)
		if(i % d == 0)
			cnt++;
	
	cout << cnt << endl;	
	return 0;
}