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#include <bits/stdc++.h>
using namespace std;
#define PII pair<int, int>
#define VI vector<int>
#define VPII vector<PII>
#define LL long long
#define LD long double
#define f first
#define s second
#define MP make_pair
#define PB push_back
#define endl '\n'      // UWAGA
#define ALL(c) (c).begin(), (c).end()
#define SIZ(c) (int)(c).size()
#define REP(i, n) for(int i = 0; i < (int)(n); ++i)
#define FOR(i, b, e) for(int i = (b); i <= (int)(e); ++i)
#define FORD(i, b, e) for(int i = (b); i >= (int)(e); --i)
#define random_shuffle(V) shuffle(V, rng)

#define sim template<class n
sim, class s> ostream & operator << (ostream &p, pair<n, s> x)
{return p << "<" << x.f << ", " << x.s << ">";}
sim> auto operator << (ostream &p, n y) ->
typename enable_if<!is_same<n, string>::value, decltype(y.begin(), p)>::type 
{int o = 0; p << "{"; for(auto c: y) {if(o++) p << ", "; p << c;} return p << "}";}
void dor() {cerr << endl;}
sim, class...s> void dor(n p, s...y) {cerr << p << " "; dor(y...);}
sim, class s> void mini(n &p, s y) {if(p>y) p = y;}
sim, class s> void maxi(n &p, s y) {if(p<y) p = y;}
#ifdef DEB
#define debug(...) dor(__FUNCTION__, ":", __LINE__, ": ", __VA_ARGS__)
#else
#define debug(...)
#endif 

#define I(x) #x " =", (x), " "
#define A(a, i) #a "[" #i " =", i, "] =", a, " "


const int MXN = 1e7+7;

int n, m, mod;
int dppoc[MXN];
int dpkon[MXN];

int dppoc_pref[MXN];
int dpkon_suf[MXN];

int dppoc_pref_suf[MXN];
int dpkon_suf_pref[MXN];

inline int nor(int x)
  {
  if(x >= mod)x -= mod;
  if(x < 0)x += mod;
  return x;
  }

LL sumpoc(int a, int b)
  {
  return nor(dppoc_pref[b] - dppoc_pref[a-1]);
  }
LL sumkon(int a, int b)
  {
  return nor(dpkon_suf[a] - dpkon_suf[b+1]);
  }


int main()
  {
  ios_base::sync_with_stdio(0);
  cin >> n >> m >> mod;

  FOR(i, 1, m)
    {
    dppoc[i] = (m-i+1);
    dpkon[i] = i;
    }

  FOR(i, 2, n+1)
    {
    FOR(j, 1, m)
      dppoc_pref[j] = nor(dppoc_pref[j-1] + dppoc[j]);
    FORD(j, m, 1)
      dpkon_suf[j] = nor(dpkon_suf[j+1] + dpkon[j]);

    FORD(j, m, 1)
      dppoc_pref_suf[j] = nor(dppoc_pref_suf[j+1] + dppoc_pref[j]);
    FOR(j, 1, m)
      dpkon_suf_pref[j] = nor(dpkon_suf_pref[j-1] + dpkon_suf[j]);
      
    if(i == n+1)break;

    FOR(j, 1, m)
      {
      dppoc[j] = nor((dppoc_pref_suf[j] - sumkon(1, j-1) * (m - j + 1)) % mod);
      dpkon[j] = nor((dpkon_suf_pref[j] - sumpoc(j+1, m) * j) % mod);
      }
    }
  int res = sumpoc(1, m);
  cout << res << endl;
  }