Cod sursa(job #3235312)

Utilizator alexvali23alexandru alexvali23 Data 16 iunie 2024 21:44:14
Problema Dirichlet Scor 0
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 0.69 kb
#include <fstream>

using namespace std;

ifstream f("dirichlet.in");
ofstream g("dirichlet.out");

const int MOD = 9999991;

int n;

int POW(int a, int b)
{
    int res = 1;
    a = a % MOD;
    while(b)
    {
        if(b & 1)
            res = res * a % MOD;
        a = a * a % MOD;
        b >>= 1;
    }
    return res;
}

int invMod(int x)
{
    return POW(x, MOD - 2);
}

int prod(int a, int b)
{
    int p = 1;
    for(int i = a; i <= b; ++i)
        p = p * i % MOD;
    return p;
}

int Combinari(int n)
{
    return (prod(n + 2, (n << 1)) * invMod(prod(1, n))) % MOD;
}

signed main()
{
    f >> n;
    g << Combinari(n) << '\n';
    return 0;
}