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#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using Pii = pair<int,int>;
using Vi = vector<int>;
#define mp make_pair
#define pb push_back
#define x first
#define y second
#define rep(i,b,e) for (int i = (b); i < (e); i++)
#define each(a,x) for (auto& a : (x))
#define all(x) (x).begin(),(x).end()
#define sz(x) int((x).size())
#define endl '\n'

const int maxM = 1e7 + 10;
int n, m, mod;
int D[2][maxM];
int U[2][maxM];
int PD[2][maxM];
int SU[2][maxM];
int PPD[2][maxM];
int SSU[2][maxM];

// vector<Vi> D, U, PD, SU, PPD, SSU;
// void resize() {
//     D.resize(2, Vi(m+2));
//     U.resize(2, Vi(m+2));
//     PD.resize(2, Vi(m+2));
//     SU.resize(2, Vi(m+2));
//     PPD.resize(2, Vi(m+2));
//     SSU.resize(2, Vi(m+2));
// }
void updateCol(int k) {
    for (int i = 1; i <= m+1; i++) {
        PD[k&1][i] = (D[k&1][i] + PD[k&1][i-1]) % mod;
        PPD[k&1][i] = (PD[k&1][i] + PPD[k&1][i-1]) % mod;
    }
    for (int i = m; i >= 0; i--) {
        SU[k&1][i] = (U[k&1][i] + SU[k&1][i+1]) % mod;
        SSU[k&1][i] = (SU[k&1][i] + SSU[k&1][i+1]) % mod;
    }
}
int getD(int k, int j) {
    ll res = j * ((ll)PD[(k-1)&1][m] - SU[(k-1)&1][j+1]) - PPD[(k-1)&1][j-1];
    return int((res % mod + mod) % mod);
}
int getU(int k, int i) {
    ll res = (m-i+1) * ((ll)PD[(k-1)&1][m] - PD[(k-1)&1][i-1]) - SSU[(k-1)&1][i+1];
    return int((res % mod + mod) % mod);
}

void solve() {
    cin >> n >> m >> mod;
    for (int i = 1; i <= m; i++) {
        D[1][i] = i % mod;
        U[1][i] = (m - i + 1) % mod;
    }
    updateCol(1);
    for (int k = 2; k <= n; k++) {
        for (int i = 1; i <= m; i++) {
            D[k&1][i] = getD(k, i);
            U[k&1][i] = getU(k, i);
        }
        updateCol(k);
    }
    cout << PD[n&1][m] << endl;
}

int main() {
    cin.sync_with_stdio(0); cin.tie(0);
    cout << fixed << setprecision(10);
    int t = 1; 
    //cin >> t;
    for (int i = 0; i < t; i++) {
        solve();
    }
}