#include "bits/stdc++.h"
using namespace std;

#define input()					freopen("C:\\Users\\safayet007\\Desktop\\in.txt", "r", stdin)
#define output()				freopen("C:\\Users\\safayet007\\Desktop\\out.txt", "w", stdout);
#define FOR(i, a, b)			for(__typeof(b) i = a; i <= b; i++)
#define REP(i, a)				for(__typeof(a) i = 0; i < a; i++)
#define REPN(i, a)				for(__typeof(a) i = 1; i <= a; i++)
#define ITERATE(it, v)			for(__typeof((v).begin()) it = (v).begin(); it != (v).end(); it++)
#define D(x)					cout << #x << " = " << (x) << endl
#define bitcount				__builtin_popcount
#define oo						(INT_MAX / 2)
#define pb						push_back
#define mp						make_pair
#define gcd						__gcd
#define endl					'\n'

typedef long long LL;
typedef pair <int, int> pii;

double f[100005];

int main (int argc, char const *argv[]) {
	//ios_base::sync_with_stdio(false);
	#ifndef ONLINE_JUDGE
 		freopen ("C:\\Users\\safayet007\\Desktop\\in.txt", "r", stdin);
		freopen ("C:\\Users\\safayet007\\Desktop\\out.txt", "w", stdout);
	#endif

	f[0] = 0.00;
	for (int i = 1; i <= 100000; i ++) {
		f[i] = f[i - 1] + log (i);
	}
	int n, r;
	while (scanf ("%d %d", &n, &r) == 2) {
		int ans = floor (f[n] - f[r] - f[n - r]) + 1;
		printf ("%d\n", ans + 1);
	}
	fflush (stdout);
	return 0;
}