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# (.NET Core 3.1.201) (judge verdict: Accepted)

using System;
using System.Linq;

namespace AtCoder.Abcdef
{
    public class QuestionA
    {
        public static void Main(string[] args)
        {
            var sw = new System.IO.StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false };
            Console.SetOut(sw);

            //Input int array
            int[] inputArray = Console.ReadLine().Split(' ').Select(i => int.Parse(i)).ToArray();
            (int L, int R, int d) = (inputArray[0], inputArray[1], inputArray[2]);

            int min = L % d == 0 ? L : L + d - L % d;

            int cnt = 0;
            int curr = min;
            while (curr <= R)
            {
                cnt++;
                curr = cnt * d + min;
            }
            Console.WriteLine(cnt.ToString());
            Console.Out.Flush();
        }
    }
}