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#include <bits/stdc++.h>
 
#define f first
#define s second
#define pb push_back
#define mp make_pair
 
#define ins insert
#define er erase
 
#define siz size()
#define siz1 size()-1
 
#define ll long long
#define ull unsigned long long
#define all(v) v.begin(), v.end()
 
#define FORN(i, n) for(int i=1; i<=(int)n; i++)
#define FOR(i,p,k) for(int i=(int)p; i<=(int)k; i++)
#define FORD(i, k, p) for(int i=(int)k; i>=(int)p; i--)
#define FOR0(i, n) for(int i=(int)n; i>=0; i--)
#define FOR1(i, n) for(int i=(int)n; i>=1; i--)
#define FORV(i, vec) for(auto i = vec.begin(); i != vec.end(); ++i)

#define TURBO ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define END cerr<<"TIME: "<<1.0 * clock() / CLOCKS_PER_SEC<<endl;
#define VI vector <int>
#define VP vector <pair<int, int>>
#define VIP vector <pair<int, pair<int, int>>>
#define VPP vector <pair<pair<int, int>, pair<int, int>>>
 
#define MII map<int, int>
#define MLL map<ll, ll>
 
#define PII pair<int, int>
#define PLL pair<ll, ll>
 
#define MAX 1e9 + 10
#define MIN -1e9 + 10

using namespace std;

int COUNT_FROM[10000000+10];
int COUNT_TO[10000000+10];
int PREFIX_COUNT_FROM[10000000+10];
int PREFIX_COUNT_TO[10000000+10];

int n, m, p; 

void COUNT_PREFIXES()
{
	PREFIX_COUNT_FROM[1] = COUNT_FROM[1];
	PREFIX_COUNT_TO[1] = COUNT_TO[1];

	for(int i=2; i<=m; i++)
	{
		PREFIX_COUNT_FROM[i] = COUNT_FROM[i] + PREFIX_COUNT_FROM[i-1];		
		PREFIX_COUNT_TO[i] = COUNT_TO[i] + PREFIX_COUNT_TO[i-1];
		
		if (PREFIX_COUNT_FROM[i] >= p)
			PREFIX_COUNT_FROM[i] -= p;

		if (PREFIX_COUNT_TO[i] >= p)
			PREFIX_COUNT_TO[i] -= p;
	}
}

void MAKE_COUNT_FROM()
{
	for(int i=1; i<=m; i++)
		COUNT_FROM[i] = COUNT_TO[m-i+1];
}

int main()
{
	TURBO;

	cin>>n>>m>>p;
	
	for(int i=1; i<=m; i++)
		COUNT_TO[i] = i % p;

	MAKE_COUNT_FROM();
	COUNT_PREFIXES();
	
	ll result = 0;
	ll diff;

	for(int pref_len=2; pref_len<=n; pref_len++)
	{
		ll all_options = PREFIX_COUNT_FROM[m];
		ll prefixowa_baza_pseudokwadratowa = 0;
		for(int konc=1; konc<=m; konc++)
		{
			prefixowa_baza_pseudokwadratowa += PREFIX_COUNT_TO[konc-1];
			if (prefixowa_baza_pseudokwadratowa >= p)
				prefixowa_baza_pseudokwadratowa -= p;
	
			result = all_options * konc;
			result %= p;
			
			result -= prefixowa_baza_pseudokwadratowa;
			diff = PREFIX_COUNT_FROM[m] - PREFIX_COUNT_FROM[konc];
			result -= diff * konc;
			
			result %= p;
			result += p;
			result %= p;

			COUNT_TO[konc] = result;
		}

		MAKE_COUNT_FROM();
		COUNT_PREFIXES();
	}

	cout<<PREFIX_COUNT_FROM[m];
	
	return 0;
}