Cod sursa(job #2170886)
Utilizator | Data | 15 martie 2018 10:13:01 | |
---|---|---|---|
Problema | Invers modular | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.58 kb |
#include <fstream>
using namespace std;
ifstream f("inversmodular.in");
ofstream g("inversmodular.out");
int a,n;
void euclid_e(long long &x, long long &y, int a, int b)
{
if(!b) x=1,y=0;
else{
euclid_e(x,y,b,a%b);
long long aux=x;
x=y;
y=aux-y*(a/b);
}
}
long long inversmodular(int a, int MOD)
{
long long inv=0, ins;
euclid_e(inv, ins, a, MOD);
if(inv<=0) inv=n+inv%MOD;
return inv;
}
int main()
{
f>>a>>n;
g<<inversmodular(a,n)<<'\n';
f.close();
g.close();
return 0;
}