Cod sursa(job #1348214)

Utilizator tudor00Stoiean Tudor tudor00 Data 19 februarie 2015 16:14:10
Problema Invers modular Scor 10
Compilator cpp Status done
Runda Arhiva educationala Marime 0.82 kb
#include <fstream>
#define NMAX 45000
using namespace std;

ifstream in("inversmodular.in");
ofstream out("inversmodular.out");

long long p1=1,p2=1,nr=1,a,n,cn,aux;
long long functie(long long a,long b)
{
    if(b==0){return 1;}
    else if(b==1){return a;}
    if(b%2==0)
    {
        long long aux;
        aux=functie(a,b/2);
        return /*(functie(a,b/2)*functie(a,b/2))%c*/(aux*aux);
    }
    if(b%2==1)
    {
        return (functie(a,b-1)*a);
    }
}
int main()
{
    in>>a>>n;
    cn=n;
    aux=2;
    while(cn!=1)
    {
        int ok=0;
        while(cn%aux==0)
        {
            ok=1;
            cn=cn/aux;
        }
        if(ok==1) {p1=p1*(aux-1);p2=p2*aux;}
        aux++;
    }
    nr=n*p1/p2;
    out<<functie(a,nr-1)%n;
    in.close();
    out.close();
    return 0;
}