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#pragma GCC optimize("O3")
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>

#define BOOST ios::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define FOR(a, b, c) for(int a = b; a < c; ++a)
#define PB push_back
#define MP make_pair
#define INF (int)1e9+7
#define LLINF 2e18+7
#define ALL(a) a.begin(), a.end()
#define SIZE(a) (int)a.size()

typedef unsigned long long ULL;
typedef long long LL;
typedef long double LD;

using namespace std;

//#define DEBUG

const int MAX = 1e7+7;

LL prefixes[MAX];
LL suffixes[MAX];
LL newPrefixes[MAX];
LL newSuffixes[MAX];    

int main()
{
    #ifndef DEBUG
    BOOST;
    #endif

    int n, m;
    LL p;

    cin >> n >> m >> p;

    FOR(i, 1, m + 1)
    {
        prefixes[i] = m - i + 1;
        suffixes[i] = i;
    }

    FOR(i, 0, n - 1)
    {
        LL prefixprefsum = 0;
        LL suffixprefsum = 0;
        LL subtract = 0;

        FOR(j, 1, m + 1)
        {
            prefixprefsum = (prefixprefsum + prefixes[j]) % p;
            subtract = (subtract - suffixprefsum + p) % p;
            suffixprefsum = (suffixprefsum + suffixes[j]) % p;

            newSuffixes[j] = ((j * prefixprefsum) % p + subtract) % p;
        }

        LL prefixsuffsum = 0;
        LL suffixsuffsum = 0;
        subtract = 0;

        for(int j = m; j >= 1; --j)
        {
            suffixsuffsum = (suffixsuffsum + suffixes[j]) % p;
            subtract = (subtract - prefixsuffsum + p) % p;
            prefixsuffsum = (prefixsuffsum + prefixes[j]) % p;

            newPrefixes[j] = ((m + 1 - j) * suffixsuffsum % p + subtract) % p;
        }

        FOR(j, 1, m + 1)
        {
            prefixes[j] = newPrefixes[j];
            suffixes[j] = newSuffixes[j];
            newSuffixes[j] = 0;
            newPrefixes[j] = 0;
        }
    }

    LL res = 0;

    FOR(i, 1, m + 1)
        res = (res + prefixes[i]) % p;

    cout << res << "\n";
 
    return 0;
}