Problem:
Score : 100 points

Problem Statement

Snuke has N integers: 1,2,\ldots,N.
He will choose K of them and give those to Takahashi.

How many ways are there to choose K consecutive integers?

Constraints

All values in input are integers.

1 \leq K \leq N \leq 50

Input

Input is given from Standard Input in the following format:

N K

Output

Print the answer.

Sample Input 1

3 2

Sample Output 1

2

There are two ways to choose two consecutive integers: (1,2) and (2,3).

Sample Input 2

13 3

Sample Output 2

11

Solution in C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<cmath>
#include<map>

using namespace std;

int main()
{
	int r, b, g, n;
	cin >> r >> b >> g >> n;;


	int ans = 0;
	for (int i = 0; i <= n; i += r)
	{

		for (int j = 0; j <= n; j += b)
		{
			int p = 0;
			p = n - (i + j);
			if (p % g == 0||p==0)
			{
				ans++;
			}
			
		}
	}
	cout << ans << endl;
}