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#include <bits/stdc++.h>
typedef long long ll;

using namespace std;

int n, m;
ll p;
struct fence{
    ll dp, c;
};
ll counter;
ll res;

int main()
{
    scanf("%d%d%lld", &n, &m, &p);
    const int r = m;
    auto tab = new fence [n*m];
    for(int i = 0; i < m; i++)
    {
        tab[i].dp = i+1;
    }
    counter = -1;
    for(int i = m-1; i >=0 ; i--)
    {
        tab[i].c = tab[i].dp;
        if(i < m-1)
        {
            tab[i].c += tab[i+1].c;
            tab[i].c %=p;
        }
        if(counter >= 0)
        {
            tab[i].c-=tab[counter].dp;
            tab[i].c +=p;
            tab[i].c %=p;
        }
        counter++;
    }
    for(int i = 1; i<n; i++)
    {
        counter = 0;
        for(int j = 0; j<m; j++)
        {
            tab[i*m+j].dp = tab[(i-1)*m+j].c*(j+1);
            tab[i*m+j].dp %= p;
            tab[i*m+j].dp+=counter;
            tab[i*m+j].dp %= p;
            counter+= tab[(i-1)*m+j].dp * (j+1);
            counter %= p;
        }
        counter = -1;
        for(int j = m-1; j>=0; j--)
        {
            tab[i*m + j].c = tab[i*m + j].dp;
            if(j < m-1)
            {
                tab[i*m + j].c += tab[i*m + j + 1].c;
                tab[i*m + j].c %= p;
            }
            if(counter >= 0)
            {
                tab[i*m + j].c-=tab[i*m + counter].dp;
                tab[i*m + j].c += p;
                tab[i*m + j].c %= p;
            }
            counter++;
        }
    }
    for(int j = 0; j<m; j++)
    {
        res+=tab[(n-1)*m+j].dp;
        res%=p;
    }
    printf("%lld", res);

}