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 Rust (1.42.0) (judge verdict: Accepted)

// https://atcoder.jp/contests/aising2020/tasks/aising2020_a

use proconio::fastout;
use proconio::input;

#[fastout]
fn main() {
    input! { l: usize, r: usize, d: usize, }
    let mut ans = 0;
    for x in l..=r {
        if x % d == 0 {
            ans += 1;
        }
    }
    println!("{}", ans);
}