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// Jenda instancja wypisuje (n * k) mod p.

#include "message.h"
#include "futbol.h"
#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <vector>
#include <set>
#include <map>
#include <cmath>
#include <ctime>
#include <queue>
#include <stack>
#include <bitset>
#include <cassert>
using namespace std;
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef long long ll;
typedef short int sint;
#define FOR(x, b, e) for(int x=(b); x<=(e); ++x)
#define FORD(x, b, e) for(int x=((int)(b))-1; x>=(e); --x)
#define REP(x, n) for(int x=0; x<(n); ++x)
#define ALL(c) c.begin(),c.end()
#define SIZE(x) ((int)((x).size()))
#define PB push_back
#define ST first
#define ND second
#define mp(x,y) make_pair(x,y)
#define DEBUG 1
#define debug(x) {if (DEBUG)cerr <<#x <<" = " <<x <<endl; }
#define debugv(x) {if (DEBUG) {cerr <<#x <<" = "; FOREACH(it, (x)) cerr <<*it <<", "; cout <<endl; }}
#define REMAX(a,b) (a)=max((a),(b));
#define REMIN(a,b) (a)=min((a),(b));
#define wez(n) int (n); scanf("%d",&(n));
#define wez2(n,m) int (n),(m); scanf("%d %d",&(n),&(m));

using namespace std;

const int N = 60000000;
int inv[N + 1];
ll n, k, p;

ll modPower(ll x, ll pot) {
	ll res = 1;
	while (pot) {
		if (pot&1) {
			res = (res * x) % p;
		}
		pot >>= 1;
		x = (x * x) %p;
	}
	return res;
}

ll getInverse(ll i) {
	return modPower(i, p - 2);
}

int main() {
  if(MyNodeId() != 0) return 0;
  n = GetN(), k = GetK(), p = GetP();
  if (k == 0 || n == k) {
  	cout << 1 << endl;
  	return 0;
  } else if (k == 1 || (n -k) == 1) {
  	cout << n << endl;
  	return 0;
  }
  ll res = n + 1;
  bool isSwitch = false;
  if (k > (n - k - 1)) {
  	isSwitch = true;
  	k = (n - k - 1);
  }
  // printf("is switch: %d\n", isSwitch);
  inv[1] = 1;
  ll ost = n;
  FOR(i, 2, k) {
  	ll odw;
  	if (i <= N) {
  		inv[i] = (p - (p/i) * inv[p%i] % p) % p;
  		odw = inv[i];
  	} else {
  		odw = getInverse(i);
  	}
  	// printf("odw[%d] = %lld\n", i, odw);
  	ost = (((ost * (n - i + 1)) % p) * odw ) % p;
  	// printf("%lld po %d = %lld\n", n, i, ost);
  	res += ost;
  }
  res %= p;
  if (isSwitch) {
  	ll pot = modPower(2, n);
  	res = (((pot - res) %p) + p) %p;
  }

  cout << res << "\n";
}