Cod sursa(job #2705473)
| Utilizator | Data | 12 februarie 2021 17:10:59 | |
|---|---|---|---|
| Problema | Invers modular | Scor | 0 |
| Compilator | cpp-64 | Status | done |
| Runda | Arhiva educationala | Marime | 0.69 kb |
#include <bits/stdc++.h>
using namespace std;
ifstream fin("inversmodular.in");
ofstream fout("inversmodular.out");
int a, b;
int exp(int a, int n)
{
long long p = 1;
while(n)
{
if(n & 1)
p = p * 1LL * a%b;
a = a * a % b;
n>>=1;
}
return p;
}
int phi(int n)
{
int ans = n;
for(int p = 2; p * p <= n; p++)
{
if(n % p == 0)
{
ans -= ans / p;
while(n % p == 0)
n/=p;
}
}
if(n > 1)
ans -= ans / n;
return ans;
}
int main()
{
fin >> a >> b;
fout << exp(a, b - 2);
fin.close();
fout.close();
return 0;
}