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#include<bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;

constexpr int M=1e7+7;

int P[M];
int P2[M];
int K[M];
int K2[M];

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	
	long long sigP, sigK, totalsig;
	int n, m, mod, res=0;
	
	cin >> n >> m >> mod;
	
	for(int j=1; j<=m; j++){
		P[j] = m-j+1;
		K[j] = j;
	}
	
	for(int i=2; i<=n; i++){
	
		sigP = sigK = totalsig = 0;
		for(int j=1; j<=m; j++){ //K
			sigP += P[j];
			if(sigP>=mod) sigP-=mod;
			
			K2[j] =  ((long long)j * sigP)%mod - totalsig;
			K2[j]%=mod;
			if(K2[j]<0) K2[j] += mod;
			
			sigK += K[j];
			if(sigK>=mod) sigK-=mod;
			totalsig += sigK;
			if(totalsig>=mod) totalsig-=mod;
		}
		
		sigP = sigK = totalsig = 0;
		for(int j=m; j>=1; j--){ //P
			sigK += K[j];
			if(sigK>=mod) sigK-=mod;
			
			P2[j] =  ((long long)(m-j+1) * sigK)%mod - totalsig;
			P2[j]%=mod;
			if(P2[j]<0) P2[j] += mod;			
			
			sigP += P[j];
			if(sigP>=mod) sigP-=mod;
			totalsig += sigP;
			if(totalsig>=mod) totalsig-=mod;			
		}
		
		for(int j=1; j<=m; j++){
			P[j] = P2[j];
			P2[j] = 0;
			
			K[j] = K2[j];
			K2[j] = 0; 
		}	
	}
	
	for(int i=1; i<=m; i++){
		res += P[i];
		if(res>=mod) res-=mod;
	}
	
	cout << res;
	
	return 0;
}