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 "math.h"
#include <iostream>
#include <fstream>
#include <algorithm>
#include <string>
#include <map>
#include <vector>
#include <functional>
#include <numeric>
#include <cmath>
using namespace std;

int t;

int main()
{
	int l, r, d;
	cin >> l >> r >> d;
	int ans = floor(r*1.0 / d) - floor(l*1.0/d);
	if (l%d == 0 && r % d == 0) ans++;
	cout << ans;
	return 0;
}