Pagini recente » Istoria paginii runda/aleatoriu/clasament | Rating andreica dumitru (dandreica) | Istoria paginii runda/test21341 | Cod sursa (job #2221045) | Cod sursa (job #1176340)
#include <stdio.h>
long long phi(long long n)
{
long long p = n;
for(long long d = 2; d*d <= n; d++)
if(n % d == 0)
{
p = p*(d-1)/d;
while(n % d == 0)
n = n/d;
}
if(n != 1) p = p / n * (n - 1);
return p;
}
long long power(long long p , long long q , long long n)
{
long long r = 1;
while (q != 0)
{
if (q % 2 == 1)
{
r = (r*p)%n;
q--;
}
p = (p*p)%n;
q = q/2;
}
return r%n;
}
int main()
{
FILE *fin = fopen("inversmodular.in" , "r");
long long a , n;
fscanf(fin , "%lld %lld" , &a , &n);
fclose(fin);
FILE *fout = fopen("inversmodular.out" , "w");
fprintf(fout , "%lld" , power(a , phi(n)-1 , n));
fclose(fout);
return 0;
}