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#define pb push_back
#define mp make_pair
#define fi first
#define se second 
#define all(...) begin(__VA_ARGS__) , end(__VA_ARGS__)
#define boost {ios_base::sync_with_stdio(false); cin.tie(); cout.tie();}

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef vector <int> vi;
typedef pair<int,int> PII;
typedef pair<ll,ll> PLL;
constexpr ll nax = 5e6+69, INF = 2e9+6969;

ll n,m,mod;
ll dp[nax],pp[nax],Dp[nax];

ll Pow(ll a, ll b)
{
	ll w = 1;
	while(b)
	{
		if(b&1) w = (w*a) % mod;
		a = (a*a) % mod;
		b >>= 1;
	}
	return w;
}

int main()
{
	scanf("%lld%lld%lld", &n, &m, &mod);
	if(n == 1)
	{
		ll ans = m*(m+1)/2;
		ans %= mod;
		printf("%lld\n", ans);
		return 0;
	}
	ll sum = 0;
	for(int i=1;i<=m;++i) dp[i] = i;
	for(int i=1;i<=m;++i) sum = (sum + dp[i]) % mod;
	for(int i=1;i<=m;++i) dp[i] = (dp[i-1] + dp[i]) % mod;
	for(int i=1;i<=m;++i) Dp[i] = (Dp[i-1] + dp[i]) % mod;
	for(int i=1;i<n;++i)
	{
		for(int j=1;j<=m;++j) 
		{
			pp[j] = (sum * j) % mod;
		}
		for(int p=1;p<=m;++p)
		{
			ll tmp = (dp[p-1] * (m-p+1) + Dp[m-p])%mod;
			pp[m-p+1] -= tmp;
			if(pp[m-p+1] < 0) pp[m-p+1] += mod;
		}
		for(int j=1;j<=m;++j) dp[j] = (pp[j] + dp[j-1])%mod;
		for(int j=1;j<=m;++j) Dp[j] = (Dp[j-1] + dp[j]) % mod;
		sum = dp[m];
	}
	printf("%lld\n", sum);
	return 0;
}