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#include <bits/stdc++.h>
using namespace std;
#define PII pair<int, int>
#define VI vector<int>
#define VPII vector<PII>
#define LL long long
#define LD long double
#define f first
#define s second
#define MP make_pair
#define PB push_back
#define endl '\n'
#define ALL(c) (c).begin(), (c).end()
#define SIZ(c) (int)(c).size()
#define REP(i, n) for(int i = 0; i < (int)(n); ++i)
#define FOR(i, b, e) for(int i = (b); i <= (int)(e); ++i)
#define FORD(i, b, e) for(int i = (b); i >= (int)(e); --i)
#define ll LL
#define st f
#define nd s
#define pb PB
#define mp MP
#define eb emplace_back
#define siz(c) SIZ(c)
const int inf = 1e9+7;
const ll INF = 1e18L+7;

#define sim template<class n
sim, class s> ostream & operator << (ostream &p, pair<n, s> x)
{return p << "<" << x.f << ", " << x.s << ">";}
sim> auto operator << (ostream &p, n y) ->
typename enable_if<!is_same<n, string>::value, decltype(y.begin(), p)>::type 
{int o = 0; p << "{"; for(auto c: y) {if(o++) p << ", "; p << c;} return p << "}";}
void dor() {cerr << endl;}
sim, class...s> void dor(n p, s...y) {cerr << p << " "; dor(y...);}
sim, class s> void mini(n &p, s y) {if(p>y) p = y;}
sim, class s> void maxi(n &p, s y) {if(p<y) p = y;}
#ifdef DEB
#define debug(...) dor(__FUNCTION__, ":", __LINE__, ": ", __VA_ARGS__)
#else
#define debug(...)
#endif 

#define I(x) #x " =", (x), " "

#ifndef LOCAL
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace __gnu_pbds;

template <typename T>
using ordered_set =
	tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

#else
#include</Users/dawid/algo/mac/ordered_set>
#endif

const int N = 1e7 + 7;
 
int n, m, mod;

int dp[2][N][2];
int pref[2][N][2];
int pref_mul[2][N][2];

inline void add(int &x, int y) {
	x += y;
	
	if (x >= mod)
		x -= mod;
	else if (x <= -mod)
		x += mod;
}

inline int mul(int x, int y) {
	return (ll) x * y % mod;
}

void add_pref(int arr[][2], int l, int r, int b, int val) {
	add(arr[l][b], val);
	add(arr[r + 1][b], -val);
}

int32_t main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(NULL);

	cin >> n >> m >> mod;

	if (n == 1) {
		cout << ((ll) m * (m + 1) / 2) % mod << endl;
		return 0;
	}

	for (int i = 1; i <= m; ++i) {
		dp[1][i][1] = (m - i + 1) % mod;
		dp[1][i][0] = (ll) (m - i + 1) * (i - 1) % mod;
	}

	for (int i = 1; i < n; ++i) {
		int dim = (i & 1);

		for (int x = 1; x <= m; ++x) {
			for (int b = 0; b < 2; ++b) {
				dp[dim ^ 1][x][b] = 0;
				pref[dim ^ 1][x][b] = 0;
				pref_mul[dim ^ 1][x][b] = 0;
			}
		}

		for (int x = 1; x <= m; ++x) {
			add_pref(pref[dim ^ 1], 1, x, 1, mul(dp[dim][x][1], (m - x + 1)));
			add_pref(pref[dim ^ 1], 1, x, 0, mul(-dp[dim][x][1], (m - x + 1)));
			add_pref(pref_mul[dim ^ 1], 1, x, 0, mul(dp[dim][x][1], (m - x + 1)));
			add_pref(pref[dim ^ 1], x + 1, m, 0, mul(mul(dp[dim][x][1], x), (m + 1)));
			add_pref(pref_mul[dim ^ 1], x + 1, m, 0, mul(-dp[dim][x][1], x));
			add(dp[dim ^ 1][x][1], mul(dp[dim][x][0], (m - x + 1)));
			add_pref(pref[dim ^ 1], x + 1, m, 0, mul(dp[dim][x][0], (m + 1)));
			add_pref(pref_mul[dim ^ 1], x + 1, m, 0, -dp[dim][x][0] % mod);
		}

		for (int x = 1; x <= m; ++x) {
			for (int b = 0; b < 2; ++b) {
				add(pref[dim ^ 1][x][b], pref[dim ^ 1][x - 1][b]);
				add(pref_mul[dim ^ 1][x][b], pref_mul[dim ^ 1][x - 1][b]);
				add(dp[dim ^ 1][x][b], pref[dim ^ 1][x][b]);
				add(dp[dim ^ 1][x][b], mul(x, pref_mul[dim ^ 1][x][b]));
			}
		}
	}

	int ans = 0;

	for (int i = 1; i <= m; ++i) {
		add(ans, mul(dp[(n - 1) & 1][i][0], (m - i + 1)));
		add(ans, mul(mul(dp[(n - 1) & 1][i][1], (m - i + 1)), i));
	}

	ans %= mod;
	ans += mod;
	ans %= mod;

	cout << ans << endl;
}