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#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
//mt19937 mrand(random_device{}()); 
const ll mod=1000000007;
//int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const int N=10100000;
int n,m,p;
int s1[N],s2[N];
int main() {
	scanf("%d%d%d",&m,&n,&p);
	for (int i=1;i<=n;i++) {
		s1[i]=(s1[i-1]+i)%p;
	}
	for (int i=1;i<m;i++) {
		ll tot=s1[n],pres=0;
		for (int r=1;r<=n;r++) {
			s2[r]=(s2[r-1]+(tot-s1[n-r])*r-pres)%p;
			pres=(pres+s1[r])%p;
		}
		rep(r,1,n+1) s1[r]=s2[r];
	}
	if (s1[n]<0) s1[n]+=p;
	printf("%d\n",s1[n]);
}