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#include <bits/stdc++.h>
using namespace std;
#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
  enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef LOCAL
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
	*this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
#else
sim dor(const c&) { ris; }
#endif
};
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
// debug & operator << (debug & dd, P p) { dd << "(" << p.x << ", " << p.y << ")"; return dd; }

int mod;

void add_self(int& a, int b) {
	a += b;
	if(a >= mod) {
		a -= mod;
	}
}

int main() {
	int w, h;
	scanf("%d%d%d", &w, &h, &mod);
	// h = 10'000'000 / w;
	if(h == 1) {
		puts("1");
		return 0;
	}
	vector<vector<int>> bottom(2, vector<int>(h));
	vector<vector<int>> middle(2, vector<int>(h));
	int cur = 0;
	for(int i = 0; i < h; ++i) {
		bottom[0][i] = 1;
	}
	for(int who = 0; who < w - 1; ++who) {
		for(int i = 0; i < h; ++i) {
			bottom[cur^1][i] = middle[cur^1][i] = 0;
		}
		// bottom -> bottom
		int pref = 0;
		for(int i = 0; i < h; ++i) {
			add_self(pref, bottom[cur][i]);
			// pref += bottom[who][i];
			bottom[cur^1][i] = (bottom[cur^1][i] + (long long) pref * (h - i)) % mod;
			// bottom[who+1][i] += pref * (h - i);
		}
		// bottom -> middle
		for(int i = 0; i < h; ++i) {
			middle[cur^1][i] = (middle[cur^1][i] + (long long) bottom[cur][i] * (h - i)) % mod;
			// middle[who+1][i] += bottom[who][i] * (h - i);
		}
		// middle -> bottom
		pref = 0;
		for(int i = 0; i < h; ++i) {
			// pref += middle[who][i] * i;
			pref = (pref + (long long) middle[cur][i] * i) % mod;
			// bottom[who+1][i] += pref * (h - i);
			bottom[cur^1][i] = (bottom[cur^1][i] + (long long) pref * (h - i)) % mod;
		}
		pref = 0;
		for(int i = h - 1; i >= 0; --i) {
			// bottom[who+1][i] += pref * (i + 1);
			bottom[cur^1][i] = (bottom[cur^1][i] + (long long) pref * (i + 1)) % mod;
			// pref += middle[who][i] * (h - i); // actually, suffix
			pref = (pref + (long long) middle[cur][i] * (h - i)) % mod;
		}
		// middle -> middle
		pref = 0;
		for(int i = h - 1; i >= 0; --i) {
			// middle[who+1][i] += pref;
			add_self(middle[cur^1][i], pref);
			pref = (pref + (long long) middle[cur][i] * (h - i)) % mod;
			// pref += middle[who][i] * (h - i); // actually, suffix
		}
		
		// for(int i = 0; i < h; ++i) {
			// for(int j = i; j < h; ++j) {
				// bottom[who+1][j] += bottom[who][i] * (h - j);
			// }
			
			// middle[who+1][i] += bottom[who][i] * (h - i);
			
			// middle -> bottom
			// for(int j = 0; j < i; ++j) {
				// bottom[who+1][j] += middle[who][i] * (h - i) * (j + 1);
			// }
			// for(int j = i; j < h; ++j) {
				// bottom[who+1][j] += middle[who][i] * i * (h - j);
			// }
			// middle -> middle
			// for(int j = 0; j < i; ++j) {
				// middle[who+1][j] += middle[who][i] * (h - i) * 1;
			// }
		// }
		cur ^= 1;
	}
	long long answer = 0;
	for(int i = 0; i < h; ++i) {
		answer = (answer + (long long) bottom[cur][i] * (h - i) + (long long) middle[cur][i] * i % mod * (h - i)) % mod;
		// answer += (long long) bottom[w-1][i] * (h - i);
		// answer += (long long) middle[w-1][i] * i * (h - i);
	}
	printf("%lld\n", answer % mod);
}