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#include <bits/stdc++.h>
#define ll long long int
#define pb push_back
#define st first
#define nd second
#define pii pair<int,int>
#define mp make_pair
#define pll pair<long long,long long>

using namespace std;

ll n,m;

vector<vector<ll> > gora,dol;

int mod;

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

    cin>>n>>m>>mod;

    gora.resize(n + 1);
    dol.resize(n + 1);
    for(int i=1;i<=n;i++)
    {
        gora[i].resize(m + 1,0);
        dol[i].resize(m + 1,0);
    }

    vector<ll> prefix_dolkow;

    for(int i=1;i<=m;i++)
    {
        gora[1][i] = (m - i + 1);
        dol[1][i] = i;
    }

    prefix_dolkow.resize(m + 1,0);
    prefix_dolkow[0] = 0;
    for(int i=1;i<=m;i++)
    {
        prefix_dolkow[i] = prefix_dolkow[i - 1] + dol[1][i];
        prefix_dolkow[i] %= mod;
    }

    int alles = prefix_dolkow[m];

    vector<ll> sufix_gorek;
    sufix_gorek.resize(m + 2,0);
    sufix_gorek[m + 1] = 0;
    for(int i=m;i>=0;i--)
    {
        sufix_gorek[i] = sufix_gorek[i + 1] + gora[1][i];
        sufix_gorek[i] %= mod;
    }

    for(int i=2;i<=n;i++)
    {
        ll sum = 0;
        for(int j=m;j>=1;j--)
        {
            ll akt = alles - prefix_dolkow[j - 1];
            if(akt < 0) akt += mod;

            sum += sufix_gorek[j + 1];
            sum %= mod;

            gora[i][j] = akt * (m - j + 1);
            gora[i][j] %= mod;
            gora[i][j] -= sum;
            if(gora[i][j] < 0) gora[i][j] += mod;
        }

        for(int j=1;j<=m;j++)
        {
            dol[i][j] = gora[i][m + 1 - j];
        }

        for(int j=1;j<=m;j++)
        {
            prefix_dolkow[j] = prefix_dolkow[j - 1] + dol[i][j];
            prefix_dolkow[j] %= mod;
        }

        for(int j=m;j>=0;j--)
        {
            sufix_gorek[j] = sufix_gorek[j + 1] + gora[i][j];
            sufix_gorek[j] %= mod;
        }

        alles = 0;
        for(int j=1;j<=m;j++)
        {
            alles += gora[i][j];
            alles %= mod;
        }
    }

    ll ans = 0;
    for(int i=1;i<=m;i++)
    {
        ans += gora[n][i];
        ans %= mod;
    }
    cout<<ans;


    return 0;
}