Nu aveti permisiuni pentru a descarca fisierul grader_test5.ok
Cod sursa(job #1569196)
| Utilizator | Data | 15 ianuarie 2016 09:04:02 | |
|---|---|---|---|
| Problema | Invers modular | Scor | 100 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.75 kb |
#include <fstream>
using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int a,n;
int Putere(int a,int k)
{
int p=1,x=a;
while(k>0)
{
if(k%2==1)
{
k--;
p=(1LL*x*p)%n;
}
k/=2;
x=(1LL*x*x)%n;
}
return p;
}
int Phi(int n)
{
int rez,d;
rez=n;
d=2;
while(n>1&&d*d<=n)
{
if(n%d==0)
{
rez=rez/d*(d-1);
while(n%d==0) n=n/d;
}
d++;
}
if(n>1) rez=rez/n*(n-1);
return rez;
}
int main()
{
fin>>a>>n;
fin.close();
int x;
x=Phi(n);
fout<<Putere(a,x-1)<<"\n";
fout.close();
return 0;
}
