Cod sursa(job #2325511)

Utilizator DumitresculEDumitrescul Eduard DumitresculE Data 22 ianuarie 2019 18:25:16
Problema Dirichlet Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 0.59 kb
#include <bits/stdc++.h>
#define mod 9999991
#define LL long long
using namespace std;
ifstream fin("dirichlet.in");
ofstream fout("dirichlet.out");
LL exponentiereRapida(LL nr, LL p){
    LL rez=1;
    while(p){
        if(p%2==1) rez=rez*nr%mod;
        nr=nr*nr%mod;
        p/=2;
    }
    return rez;
}
int x[105];
int main()
{
    LL n,fact_n=1,fact_2n=1,i;
    fin>>n;
    for(i=1;i<=n;i++)
        fact_n=fact_n*i%mod;
    fact_2n=1;
    for(i=n+2;i<=2*n;i++)
        fact_2n=fact_2n*i%mod;
    fout<<fact_2n*exponentiereRapida(fact_n,mod-2)%mod<<"\n";
    return 0;
}