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#include<bits/stdc++.h>
using namespace std;
using LL = long long;
using D = double;
#define f1 first
#define f2 second
#define randint(a, b) uniform_int_distribution<int>{a, b}(gen)
#ifdef LOC
void OUT() {cout << '\n';}
template<class H, class ... T> void OUT(H h, T ... t)
{
	cout << h << ' ';
	OUT(t...);
}
#define P(...) cout << "[" << #__VA_ARGS__ << "] ", OUT(__VA_ARGS__)
#else
#define P(...)
#define OUT(...)
#endif
int n, m, p;
vector<LL> dp[2];

LL add(LL a, LL b)
{
	a += b;
	if(a >= p) a -= p;
	return a;
}

LL subtract(LL a, LL b)
{
	a -= b;
	if(a < 0) a += p;
	return a;
}

void oper()
{
	LL val = 0;
	for(LL i = 0; i < m; ++i)
	{
		val = add(val, (dp[0][i] * (i + 1)) % p);
	}
	LL sum = 0;
	LL revSum = 0;
	for(LL i = m - 1; i >= 0; --i)
	{
		dp[1][i] = subtract(val, revSum * (i + 1) % p);
		sum = add(dp[0][i], sum);
		revSum = add(revSum, dp[0][m - 1 - i]);
		val = subtract(val, sum);
	}
#ifdef LOC
	for(int i = 0; i < m; ++i)
		cout << dp[1][i] << ' ';
	cout << '\n';
#endif
	swap(dp[0], dp[1]);
}

int main(int, char ** /*args*/)
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cin >> n >> m >> p;
	dp[0].resize(m, 0);
	dp[1].resize(m, 0);
	for(int i = 0; i < m; ++i)
	{
		dp[0][i] = i + 1;
	}
	while(--n)
	{
		oper();
	}
	LL ans = 0;
	for(int i = 0; i < m; ++i)
	{
		ans = add(ans, dp[0][i]);
	}
	cout << ans % p << '\n';
	return 0;
}