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 pair<int,int> pii;
typedef vector<int> vec;
typedef unordered_map<int,int> hash;
#define long long long
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define sz(x) (int)x.size()
#define F first
#define S second
#define pb push_back
#define mp make_pair
#define fill(a,v) memset(a,v,sizeof(a))
#define FOR(i, a, b) for(int i = a; i < b; i++)
#define INF 0x3f3f3f3f//infinity for integers
#define JJ ios_base::sync_with_stdio(0); cin.tie(0)//input fast
#define MOD 1000000007


int main()
{
	JJ;
	int l,r,d; cin>>l>>r>>d;
	int ans=0;
	FOR(i,l,r+1){
		if(i%d==0)
			ans++;
	}
	cout<<ans<<endl;
	


	return 0;
}