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#include <iostream>
#include <vector>

using namespace std;

typedef long long ll;

int m, n;
ll p;

ll mod(ll v) {
    return ((v % p) + p) % p;
}

int brute(int a, int b, int l) {
    if (l == 0) return 1;
    int acc = 0;
    for (int x = 1;x <= b;x++) {
        for (int y = max(a, x);y <= m;y++) {
            acc += brute(x, y, l - 1);
        }
    }

    return acc;
}

ll** arr;
ll* arr_ex;

void metrix_update() {
    arr_ex[0] = arr[0][0];
    //cout << arr_ex[0] << " ";
    for (int j = 1;j < m;j++) {
        ll a = 0;
        for (int i = 0;i <= j;i++)
            a += arr[i][j];
        arr_ex[j] = mod(a + arr_ex[j - 1]);
       // cout << arr_ex[j] << " ";
    }
    //cout << "\n";
}

void printAcc(int** a) {
    for (int i = 0;i < m;i++) {
        for (int j = 0;j < m;j++)
            cout << a[i][j] << " ";
        cout << "\n";
    }
}

ll get_ex(int i) {
    if (i <= 0) return 0;
    return arr_ex[i-1];
}

void addOne() {
    metrix_update();
    for (int i = 0;i < m;i++)
        for (int j = i;j < m;j++) {
            arr[i][j] = mod(arr_ex[m - 1] - get_ex(i) - get_ex(m - j - 1));
        }
}

ll sol() {
    arr = new ll * [m];
    arr_ex = new ll[m];

    for (int i = 0;i < m;i++) {
        arr[i] = new ll[m] {0};
    }

    for (int i = 0;i < m;i++)
        for (int j = i;j < m;j++) {
            arr[i][j] = 1;
        }

    //printAcc(arr);

    for (int k = 1;k < n;k++)
        addOne();

    metrix_update();

    //printAcc(arr);

    return arr_ex[m-1];
}



int main()
{
    cin >> n >> m >> p;
    //cout << brute(1, m, n) << "\n";
    cout << sol();
}