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#include <bits/stdc++.h>
using namespace std;

#define endl '\n'
#define L long long
#define MP make_pair
#define REP(i, n) for(int i = 0; i < n; ++i)
#define REPR(i, n) for(int i = n - 1; i >= 0; --i)
#define FOR(i, a, b) for(int i = a; i < b; ++i)
#define FORR(i, a, b) for(int i = b - 1; i >= a; --i)
#define EB emplace_back
#define ST first
#define ND second
#define S size()
#define RS resize

using VI = vector<int>;
using VVI = vector<VI>;
using PI = pair<int, int>;
using VPI = vector<PI>;
using VVPI = vector<VPI>;
using VL = vector<L>;
using VVL = vector<VL>;
using VB = vector<bool>;
using VC = vector<char>;

L p;

void mod(L &a)
{
    if (a >= p)
        a -= p;
}

void mod2(L &a)
{
    if (a >= p)
        a %= p;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    int n, m;
    cin >> n >> m >> p;
    L sp = p * p;
    
    VVL pref(n, VL(m + 1)), pref2(n, VL(m + 1));
    
    FOR(i, 1, m + 1)
    {
        pref[0][i] = pref[0][i - 1] + (L)i;;
        mod2(pref[0][i]);
        pref2[0][i] = pref2[0][i - 1] + pref[0][i];
        mod(pref2[0][i]);
    }
    
    FOR(i, 1, n)
        FOR(d, 1, m + 1)
        {
            pref[i][d] = pref[i][d - 1] + (L)d * (pref[i - 1][m] - pref[i - 1][m - d]) - pref2[i - 1][d - 1] + sp;
            mod2(pref[i][d]);
            pref2[i][d] = pref2[i][d - 1] + pref[i][d];
            mod(pref2[i][d]);
        }
    
    cout << pref[n - 1][m];
}