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;
using System.Collections;
using System.Collections.Generic;
using System.Linq.Expressions;

namespace Main
{
    class Program
    {
        static void Main(string[] args)
        {
            //ここから
            //int n=Readint();
            //string[] str = Console.ReadLine().Split(' ');
            string[] str = Console.ReadLine().Split(' ');

            int l = int.Parse(str[0]);
            int r = int.Parse(str[1]);
            int d = int.Parse(str[2]);

            int count = 0;
            for(int i = l; i <= r; i++)
            {
                if (i % d == 0) count++;
            }

            Cout(count);

            //ここまで
        }

        static void Cout(string s)
        {
            Console.WriteLine(s);
            return;
        }

        static void Cout(int n)
        {
            Console.WriteLine(n);
            return;
        }

        static void Cout(long n)
        {
            Console.WriteLine(n);
            return;
        }

        static int Readint()
        {
            return int.Parse(Console.ReadLine());
        }

        static int[] ReadArray(int n)
        {
            string[] str = Console.ReadLine().Split(' ');
            int[] a = new int[n];
            for (int i=0; i < n; i++){ a[i] = int.Parse(str[i]); }
            return a;
        }
        static long[] ReadArray(long n)
        {
            string[] str = Console.ReadLine().Split(' ');
           long[] a = new long[n];
            for (long i = 0; i < n; i++) { a[i] = long.Parse(str[i]); }
            return a;
        }

        static long Readlong()
        {
            return long.Parse(Console.ReadLine());
        }

        static int Min(int a, int b)
        {
            if (a < b) return a;
            return b;
        }

        static int Max(int a, int b)
        {
            if (a > b) return a;
            return b;
        }


    }

}