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//42

#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

typedef uint32_t ul;
typedef int32_t l;
typedef uint64_t ull;
typedef int64_t ll;

template <typename T>
using statistics_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

const l INF = 1000000000 + 9;
const l PRIME = 200003;
const ll L_INF = 1000000000000000000LL + 7;
const double EPS = 1e-5;

#define FOR(x, y, z) for (l z = x; z < y; z++)
#define FORE(x, y, z) for (l z = x; z <= y; z++)
#define FORD(x, y, z) for (l z = x; z > y; z--)
#define FORDE(x, y, z) for (l z = x; z >= y; z--)
#define REP(x, y) for (l y = 0; y < x; y++)
#define ALL(...) (__VA_ARGS__).begin(), (__VA_ARGS__).end()

#define PF push_front
#define POF pop_front
#define PB push_back
#define POB pop_back
#define MP make_pair
#define FS first
#define SC second

const l MAXN = 1000005;

l n, m, idx=1;
ll MOD;

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr);

    cin >> n >> m >> MOD;

    ll **dp[2];
    dp[0] = new ll*[m+1];
    dp[1] = new ll*[m+1];

    ll* acc = new ll[m+1];
    ll* suffix_sum = new ll[m+1];

    FORE(0, m, i)
    {
        dp[0][i] = new ll[m+1];
        dp[1][i] = new ll[m+1];
    }    

    FORE(1, m, i)
    {
        FORE(i, m, j)
        {
            dp[0][i][j] = 1;
            acc[i] += 1;
            acc[j+1] -= 1;
        }

        suffix_sum[i] = m-i+1;
    }

    FORE(2, n, k)
    {
        FORE(1, m, i)
            FORE(i, m, j)
                dp[idx][i][j] = 0;

        ll score{0};
        FORE(1, m, i)
        {
            score += acc[i];
            dp[idx][i][i] = score;
            acc[i] = 0;
        }

        FORE(1, m, i)
            FORE(i+1, m, j)
            {
                dp[idx][i][j] = (dp[idx][i][j-1] + suffix_sum[j])%MOD;
            }

        if(k != n)
        {
            FORE(1, m, i)
            {
                suffix_sum[i] = 0;

                FORE(i, m, j)
                {
                    acc[i] = (acc[i] + dp[idx][i][j])%MOD;
                    acc[j+1] = ((acc[j+1] - dp[idx][i][j])%MOD + MOD)%MOD;
                    suffix_sum[i] = (suffix_sum[i] + dp[idx][i][j])%MOD;
                }
            }
        }

        idx = (idx+1)%2;
    }

    ll res{0};
    FORE(1, m, i)
        FORE(i, m, j)
            res = (res+dp[(idx-1+2)%2][i][j])%MOD;

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