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.Collections.Generic;
//using System.Linq;
//using System.Numerics;

class Program {
    static void Main (string[] args) {
        var input = INP();
        int L = TOI(input[0]);
        int R = TOI(input[1]);
        int d = TOI(input[2]);

        int cnt = 0;
        for(int i = L;i < R + 1;i++) {
            if(i % d == 0) {
                cnt++;
            }
        }

        CWL(cnt);
    }


    public static List<int> PrimeFactors (int n) {
        var tmpList = new List<int>();
        int i = 2;
        int tmp = n;

        while(i * i <= n) {
            if(tmp % i == 0) {
                tmp /= i;
                tmpList.Add(i);
            } else {
                i++;
            }
        }

        if(tmp != 1) tmpList.Add(tmp);

        return tmpList;
    }

    static string[] INP () {
        return Console.ReadLine().Split(' ');
    }

    static void CWL (string value) {
        Console.WriteLine(value);
    }

    static void CWL (int value) {
        Console.WriteLine(value);
    }

    static void CWL (long value) {
        Console.WriteLine(value);
    }

    static void CWL (float value) {
        Console.WriteLine(value);
    }

    static void CWL (double value) {
        Console.WriteLine(value);
    }

    static int TOI (string str) {
        return int.Parse(str);
    }

    static long TOL (string str) {
        return long.Parse(str);
    }

    static float TOF (string str) {
        return float.Parse(str);
    }

    static double TOD (string str) {
        return double.Parse(str);
    }

    /*static void Main (string[] args) {
        var input = INP();
        var input2 = INP();
        var input3 = INP();

        CWL("dummy");
    }*/
}