#include <bits/stdc++.h>
#define ADD(a, b) a = (a + ll(b)) % mod
#define MUL(a, b) a = (a * ll(b)) % mod
#define MAX(a, b) a = max(a, b)
#define MIN(a, b) a = min(a, b)
#define rep(i, a, b) for(int i = int(a); i < int(b); i++)
#define rer(i, a, b) for(int i = int(a) - 1; i >= int(b); i--)
#define all(a) (a).begin(), (a).end()
#define sz(v) (int)(v).size()
#define pb push_back
#define sec second
#define fst first
#define debug(fmt, ...) Debug(__LINE__, ":", fmt, ##__VA_ARGS__)
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<int, pi> ppi;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<vl> mat;
typedef complex<double> comp;
void Debug() {cerr << '\n'; }
template<class FIRST, class... REST>void Debug(FIRST arg, REST... rest){
	cerr<<arg<<" ";Debug(rest...);}
template<class T>ostream& operator<<(ostream& out,const vector<T>& v) {
	out<<"[";if(!v.empty()){rep(i,0,sz(v)-1)out<<v[i]<<", ";out<<v.back();}out<<"]";return out;}
template<class S, class T>ostream& operator<<(ostream& out,const pair<S, T>& v){
	out<<"("<<v.first<<", "<<v.second<<")";return out;}
const int MAX_N = 500010;
const int MAX_V = 100010;
const double eps = 1e-6;
const int inf = (1 << 30) - 1;
const ll linf = 1LL << 60;
const double PI = 3.14159265358979323846;
mt19937 rng; //use it by rng() % mod, shuffle(all(vec), rng)
///////////////////////////////////////////////////////////////////////////////////////////////////

int N;
ll mod;
// ll dp[2][5010][5010];
ll C[5010][5010], D[5010][5010];

//x^K/(1-x)(1-x^2)...(1-x^L)??


void solve() {
	cin >> N >> mod;

	D[0][0] = 1;
	rep(i, 0, N / 2) {
		rep(j, 0, N + 1) {
			D[i + 1][j] = D[i][j];
		}
		rep(j, 0, N + 1) {
			if(j + i + 1 <= N) ADD(D[i + 1][j + i + 1], D[i + 1][j]);
		}
	}
	rep(i, 0, N / 2 + 1) {
		rep(j, 0, N + 1) {
			ADD(D[i][j + 1], D[i][j]);
		}
	}
	rep(n, 0, N) {
		rep(k, 1, N + 1) {
			if(n == 0 || k == 1) C[k][n] = 1;
			else {
				C[k][n] = (C[k - 1][n] + (k > n ? 0 : C[k][n - k])) % mod;
			}
		}
	}
	rep(k, 1, N + 1) {
		rep(n, 0, N) {
			ADD(C[k][n + 1], C[k][n]);
		}
	}

	auto get_val = [&](int L, int K, int S){
		if(L >= S) {
			return (D[K][S] - (S > 0 ? D[K][S - 1] : 0) + mod) % mod;
		}
		else {
			if(L == 1) {
				if(S <= K) return 1ll;
				else return 0ll;
			}
			else return (2 * mod + (C[L][S] - C[L][S - 1]) - (S - K - 1 < 0 ? 0 : C[L - 1][S - K - 1])) % mod;
		}
	};

	// int now = 0, nex = 1;
	//
	// dp[now][0][0] = 1;
	//
	// rep(i, 0, N / 2) {
	// 	rep(j, 0, N) {
	// 		if((N / 2 - 1 - i - 1) * j <= N) memset(dp[nex][j], 0, sizeof(dp[nex][j]));
	// 	}
	// 	rep(j, 0, N) {
	// 		rep(k, 0, N) {
	// 			if((N / 2 - 1 - i) * j + k > N || dp[now][j][k] == 0) continue;
	// 			if(k + j <= N) ADD(dp[nex][j][k + j], dp[now][j][k]);
	// 			ADD(dp[now][j + 1][k], dp[now][j][k]);
	// 			debug(i, j, k, dp[now][j][k]);
	// 		}
	// 	}
	// 	swap(nex, now);
	// }
	// rep(j, 0, N) {
	// 	rep(k, 0, N) {
	// 		if(dp[now][j][k] == 0) continue;
	// 		ADD(dp[now][j + 1][k], dp[now][j][k]);
	// 		debug(N / 2, j, k, dp[now][j][k]);
	// 	}
	// }
	// rep(i, 0, 2) {
	// 	rep(j, 0, N) {
	// 		rep(k, 0, N) {
	// 			ADD(dp[i][j][k + 1], dp[i][j][k]);
	// 		}
	// 	}
	// }
	ll res = 0;
	rep(a, 0, N) {
		rep(b, 0, a + 1) {
			if(N % 2 == 1) {

				// debug(N - 1 - a, N / 2, a - b, dp[now][a][b], D[N / 2][b], (dp[now][N - 1 - a][a - b] - (a - b != 0 ? dp[now][N - 1 - a][a - b - 1] : 0) + mod) % mod, 
						// get_val(N - 1 - a, N / 2, a - b));
				// ADD(res, (dp[now][a][b] - (b != 0 ? dp[now][a][b - 1] : 0) + mod) % mod * dp[now][N - 1 - a][a - b] % mod);
				ADD(res, get_val(N - 1 - a, N / 2, b) * D[N / 2][a - b] % mod);
			}
			else {
				// ADD(res, (dp[now][a][b] * (dp[nex][N - 1 - a][a - b] - (a - b != 0 ? dp[nex][N - 1 - a][a - b - 1] : 0) + mod) % mod));
				// debug(N - 1 - a, N / 2 - 1, a - b, dp[now][a][b], D[N / 2][b], (dp[nex][N - 1 - a][a - b] - (a - b != 0 ? dp[nex][N - 1 - a][a - b - 1] : 0) + mod) % mod, 
						// get_val(N - 1 - a, N / 2 - 1, a - b));
				ADD(res, get_val(N - 1 - a, N / 2 - 1, a - b) * D[N / 2][b] % mod);
			}
		}
	}
	cout << res << "\n";
}

uint32_t rd() {
	uint32_t res;
#ifdef __MINGW32__
	asm volatile("rdrand %0" :"=a"(res) ::"cc");
#else
	res = std::random_device()();
#endif
	return res;
}

int main() {
#ifndef LOCAL
	ios::sync_with_stdio(false);
    cin.tie(0);
#endif
    cout << fixed;
	cout.precision(20);
    cerr << fixed;
	cerr.precision(6);
	rng.seed(rd());
#ifdef LOCAL
	//freopen("in.txt", "wt", stdout); //for tester
	if(!freopen("in.txt", "rt", stdin)) return 1;
#endif	
	solve();
    cerr << "Time: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
	return 0;
}



Measured memory_bytes: 295808