Pagini recente » Cod sursa (job #2650633) | Cod sursa (job #18288) | Cod sursa (job #1958586) | Cod sursa (job #2863935) | Cod sursa (job #2279988)
#include <fstream>
#define M 9999991
using namespace std;
ifstream f("dirichlet.in");
ofstream g("dirichlet.out");
long long putere(long long x,long long n)
{
if(n==0)return 1;
if(n==1)return x;
long long a = putere(x,n/2);
if(n%2==0)
{
return ((a*a)%M);
}
else
{
return (((a*x)%M)*a)%M;
}
}
long long comb(long long n,long long k)
{
long long r=1,t=1;
for(int i=2;i<=n;++i)
{
r = (r*i)%M;
if(i<=k)t = (t*i)%M;
if(i<=n-k)t=(t*i)%M;
}
t = t*(k+1);
r = (r*putere(t,M-2))%M;
return r;
}
long long n;
int main()
{
f>>n;
g<<comb(2*n,n);
return 0;
}