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#include "bits/stdc++.h" // Tomasz Nowak
using namespace std;     // XIII LO Szczecin
using LL = long long;    // Poland
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
template<class T> int size(T &&x) {
	return int(x.size());
}
template<class A, class B> ostream& operator<<(ostream &out, const pair<A, B> &p) {
	return out << '(' << p.first << ", " << p.second << ')';
}
template<class T> auto operator<<(ostream &out, T &&x) -> decltype(x.begin(), out) {
	out << '{';
	for(auto it = x.begin(); it != x.end(); ++it)
		out << *it << (it == prev(x.end()) ? "" : ", ");
	return out << '}';
}
void dump() {}
template<class T, class... Args> void dump(T &&x, Args... args) {
	cerr << x << ";  ";
	dump(args...);
}
#ifdef DEBUG
  struct Nl{~Nl(){cerr << '\n';}};
# define debug(x...) cerr << (strcmp(#x, "") ? #x ":  " : ""), dump(x), Nl(), cerr << ""
#else
# define debug(...) 0 && cerr
#endif
mt19937_64 rng(0);
int rd(int l, int r) {
	return uniform_int_distribution<int>(l, r)(rng);
}
// end of templates

int p;

int add(int a, int b) {
	a += b;
	if(a >= p)
		a -= p;
	return a;
}
int sub(int a, int b) {
	return add(a, p - b);
}
int mul(int a, int b) {
	return int((a * LL(b)) % p);
}

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

	int n, m;
	cin >> n >> m >> p;
	vector dp(n, vector<int>(m + 1, 0));
	REP(r, m + 1)
		dp[0][r] = int((r * LL(r + 1) / 2) % p);

	for(int c = 1; c < n; ++c) {
		vector<int> add_to_suffix(m + 1);
		for(int r = 1; r <= m; ++r)
			add_to_suffix[r] = add(add_to_suffix[r], mul(dp[c - 1][m], r));
		vector<int> double_prefix(m + 1);
		for(int l = 1; l <= m; ++l)
			double_prefix[l] = dp[c - 1][l - 1];
		for(int l = 1; l <= m; ++l)
			double_prefix[l] = add(double_prefix[l], double_prefix[l - 1]);
		for(int l = 1; l <= m; ++l)
			add_to_suffix[l] = sub(add_to_suffix[l], double_prefix[l]);
		for(int r = 1; r <= m; ++r)
			add_to_suffix[r] = sub(add_to_suffix[r], mul(r, dp[c - 1][m - r]));
		for(int r = 1; r <= m; ++r)
			add_to_suffix[r] = add(add_to_suffix[r], add_to_suffix[r - 1]);
		dp[c] = add_to_suffix;
	}
	debug(dp);
	cout << dp[n - 1][m] << '\n';
	// system("grep Peak /proc/$PPID/status");
}