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<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<cmath>
#include<queue>
#include<stack>
#include<map>
#include<numeric>

using namespace std;

#define rep(i, n) for (int i = 0; i < (int)(n); i++)

template<typename A, typename B> bool chmin(A &a, const B &b){ return b < a && (a = b, true); }
template<typename A, typename B> bool chmax(A &a, const B &b){ return a < b && (a = b, true); }

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