//#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4.1,sse4.2,avx,avx2,popcnt,tune=native")
//#pragma GCC optimize(2)
#include<cstdio>
#include<iostream>
#include<string>
#include<cstring>
#include<map>
#include<cmath>
#include<cctype>
#include<vector>
#include<set>
#include<queue>
#include<algorithm>
#include<sstream>
#include<ctime>
#include<cstdlib>
#define X first
#define Y second
#define L (u<<1)
#define R (u<<1|1)
#define pb push_back
#define mk make_pair
#define Mid (tr[u].l+tr[u].r>>1)
#define Len(u) (tr[u].r-tr[u].l+1)
#define random(a,b) ((a)+rand()%((b)-(a)+1))
#define db puts("---")
using namespace std;

//void rd_cre() { freopen("d://dp//data.txt","w",stdout); srand(time(NULL)); }
//void rd_ac() { freopen("d://dp//data.txt","r",stdin); freopen("d://dp//AC.txt","w",stdout); }
//void rd_wa() { freopen("d://dp//data.txt","r",stdin); freopen("d://dp//WA.txt","w",stdout); }

typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int,int> PII;

const int N=510,INF=0x3f3f3f3f;
const double eps=1e-6;

int n,mod;
LL c[N][N],pow2[N];
LL f[N][N];

int main()
{
//	ios::sync_with_stdio(false);
//	cin.tie(0);

	scanf("%d%d",&n,&mod);
	pow2[0]=1;
	for(int i=1;i<N;i++) pow2[i]=pow2[i-1]*2%mod;
	for(int i=0;i<N;i++)
		for(int j=0;j<=i;j++)
		{
			if(j==0) { c[i][j]=1; continue; }
			c[i][j]=c[i-1][j-1]+c[i-1][j]; 
			c[i][j]%=mod;
		}
	f[0][0]=1;
	for(int len=0;len<n;len++)
		for(int cnt=0;cnt<=len;cnt++)
			for(int k=1;k+len<=n;k++)
				(f[len+k+1][cnt+k]+=f[len][cnt]*c[cnt+k][k]%mod*pow2[k-1]%mod)%=mod;
	/*
	for(int i=0;i<n;i++)
		for(int j=0;j<=i;j++)
			for(int k=1;k+i<=n;k++)
				f[i+k+1][j+k]=(f[i+k+1][j+k]+f[i][j]*pow2[k-1]%mod*c[k+j][j])%mod;
	*/
	LL ans=0;
	for(int i=0;i<=n;i++) (ans+=f[n+1][i])%=mod;
	printf("%lld\n",ans);



	return 0;
}
/*

*/








