#include<iostream>
#include<cstdio>
#include<cstring>
#define ll long long
using namespace std;
ll n;//
ll p;
ll f[2][4205];
int main(){
scanf("%lld%lld",&n,&p);//
if(p==0){
puts("0");
return 0;
}
f[2&1][2]=(ll)1;
for(int i=3;i<=n;++i){
for(int j=2;j<=n;++j){
f[i&1][j]=(f[i&1][j-1]+f[(i-1)&1][(i-1)-(j-1)+1])%p;
// f[i&1][j]=(f[i&1][j-1]+f[(i-1)&1][(i-1+1)-(j-1)])%p;
// cout<<i<<" "<<j<<" "<<f[i&1][j]<<" "<<f[i&1][j-1]<<" "<<f[(i-1)&1][(i-1+1)-(j-1)]<<endl;
}
}
ll ans=0;
for(int i=1;i<=n;++i){//
ans=(ans+f[n&1][i])%p;
}
printf("%lld\n",ans*(ll)2%p);//
return 0;
}
