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 <bits/stdc++.h>
using namespace std;
#define endl "\n"
#define int long long
#define pb push_back
#define all(v) v.begin(),v.end()
#define tc int tcs;cin>>tcs;while(tcs--)
const int N=200007;
const int MOD=1e9+7;
// lower_bound - which does not compare less than val
// upper_bound - which compares greater than val
int a[N],b[N];
vector<int> v(N);
#define trace1(x)                cerr<<#x<<": "<<x<<endl
#define trace2(x, y)             cerr<<#x<<": "<<x<<" | "<<#y<<": "<<y<<endl
#define trace3(x, y, z)          cerr<<#x<<":" <<x<<" | "<<#y<<": "<<y<<" | "<<#z<<": "<<z<<endl
#define trace4(a, b, c, d)       cerr<<#a<<": "<<a<<" | "<<#b<<": "<<b<<" | "<<#c<<": "<<c<<" | "<<#d<<": "<<d<<endl
#define trace5(a, b, c, d, e)    cerr<<#a<<": "<<a<<" | "<<#b<<": "<<b<<" | "<<#c<<": "<<c<<" | "<<#d<<": "<<d<<" | "<<#e<< ": "<<e<<endl
#define printclock cerr<<"Time : "<<1000*(int)clock()/(int)CLOCKS_PER_SEC<<"ms\n"


int32_t main()
{
  
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  /* stuff you should look for
  * int overflow, array bounds
  * special cases (n=1?)
  * do smth instead of nothing and stay organized
*/


int a,b,c;
cin>>a>>b>>c;
int count=0;
for(int i=a;i<=b;i++)
{
	if(i%c==0)
	count++;
}
cout<<count;


cout<<endl;
printclock;
}