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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<bool> vb;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef vector<ll> vl;
typedef vector<vector<ll>> vvl;
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define mt make_tuple
#define st first
#define nd second
#define FOR(__VAR, __START, __END) for(int __VAR=__START; __VAR<=__END; __VAR++)
#define FORB(__VAR, __START, __END) for(int __VAR=__START; __VAR>=__END; __VAR--)
#define FORK(__VAR, __START, __END, __DIFF) for(int __VAR=__START; __VAR<=END; __VAR+=__DIFF)
#define all(__VAR) (__VAR).begin(), (__VAR).end()
#define rall(__VAR) (__VAR).rbegin(), (__VAR).rend()
#define DEBUG(__VAR) cout << #__VAR << ": " << __VAR << endl;

template<typename __T1, typename __T2>
ostream & operator<<(ostream &out, pair<__T1, __T2> &__VAR)
{
	cout << "[" << __VAR.st << ", " << __VAR.nd << "]";
	return out;
}

template<typename __T>
ostream & operator<<(ostream &out, vector<__T> &__VAR)
{
	cout << "[";
	FOR(i, 0, (int)__VAR.size()-2)
		cout << __VAR[i] << ", ";
	if(__VAR.size()>0)
		cout << __VAR[__VAR.size()-1];
	cout << "]" << endl;
	
	return out;
}

const int INF=1e9;

void getPref(vector<vector<ll>>& v, ll MOD) {
	int m=v.size();
	for(int i=1; i<m; i++) {
		v[i][0]=(v[i-1][0]+v[i][0])%MOD;
		v[0][i]=(v[0][i-1]+v[0][i])%MOD;
	}
	for(int i=1; i<m; i++)
		for(int j=1; j<m; j++)
			v[i][j]=(v[i-1][j]+v[i][j-1]-v[i-1][j-1]+v[i][j]+MOD)%MOD;
}

int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);

	ll n,m, MOD;
	cin >> n >> m >> MOD;
	vector<vector<ll>> dp(m+1, vector<ll>(m+1, 0LL));
	vector<vector<ll>> prev(m+1, vector<ll>(m+1, 0LL));
	for(int i=1; i<=m; i++)
		for(int j=i; j<=m; j++)
			prev[i][j]=1LL;	
	getPref(prev, MOD);
	for(int i=2; i<=n; i++) {
		for(int j=0; j<=m; j++)
			fill(dp[j].begin(), dp[j].end(), 0LL);
		
		for(int l=1; l<=m; l++)
			for(int r=l; r<=m; r++)
				dp[l][r]=(prev[r][m]-prev[r][l-1]+MOD)%MOD;
		prev=dp;
		getPref(prev, MOD);	
	}
	cout << prev[m][m] << '\n';

	return 0;
}