Cod sursa(job #527871)

Utilizator ioanabIoana Bica ioanab Data 1 februarie 2011 14:24:27
Problema Suma divizorilor Scor 30
Compilator cpp Status done
Runda Arhiva de probleme Marime 1 kb
#include <cstdio>
using namespace std;

const int N=1000005;
bool c[N];
int v[N];


void ciur()
{
	int i,j,n;
	for(i=2;i*i<N;++i)
		if(!c[i])
			for(j=i*i;j<N;j+=i)
				c[j]=true;
	n=0;
	for(i=2;i<N;i++)
		if(c[i]==false)
			v[++n]=i;
}

long long Fast_pow(long long a, long long b)
{
	long long p;
	if(b==0)
		return 1;
	if(b==1)
		return a;
	p=Fast_pow(a%9901,b/2);
	if(b%2==0)
		return (p%9901 * p%9901)%9901;
	if(b%2==1)
		return (((p%9901* p%9901)%9901)*a%9901)%9901;
	return 0;
}


int main()
{
	freopen("sumdiv.in","r",stdin);
	freopen("sumdiv.out","w",stdout);
	int i,p;
	long long suma,a,b;
	ciur();
	scanf("%lld%lld",&a,&b);
	suma=1;
		
	for(i=1;v[i]*v[i]<=a;++i)
		if(a%v[i]==0)
		{
				p=0;
				while(a%v[i]==0)
				{
					++p;
					a/=v[i];
				}
				suma=suma*(Fast_pow(v[i],p*b+1)-1)/(v[i]-1);
				suma=suma%9901;
		}
	
		if(a!=1)
		{
			suma=suma*(Fast_pow(a,b+1)-1)/(a-1);
			suma=suma%9901;
		}
		printf("%lld\n",suma);

	return 0;
}