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#include <cstdio>
#include <cmath>
using namespace std;
bool prim (long long int x)
{
int i;
for (i=2; i*i<=x; i++)
if (x%i==0) return false; return true;
}
int sol (long long int nr)
{
long long int i, x=nr;
for (i=2; i*i<=nr; i++)
{
if (nr%i==0)
{
while (nr%i==0) nr/=i;
x=(x/i)*(i-1);
}
}
if (nr!=1) x=(x/nr)*(nr-1);
return x;
}
void euclid (long long int a, long long int b, long long int &x, long long int &y)
{
if (b==0)
{
x=1; y=0;
}
else
{
euclid(b,a%b,x,y);
long long int aux;
aux=x;
x=y;
y=aux-y*(a/b);
}
}
int main()
{
long long int a, n, i;
freopen("inversmodular.in","r",stdin);
freopen("inversmodular.out","w",stdout);
scanf("%lld%lld",&a,&n);
if (prim(n))
{
long long int put=sol(n)-1, nr=a, x=1, p;
for (p=1; p<=put; p<<=1)
{
if (p&put) x=(x*nr)%n;
nr=(nr*nr)%n;
}
printf("%lld",x);
}
else
{
long long int x=0, y;
euclid(a,n,x,y);
if (x<=0) x=n+x%n;
printf ("%lld",x);
}
fclose(stdin);
fclose(stdout);
return 0;
}