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#include <iostream>
#include<bits/stdc++.h>
using namespace std;
long long N,P;
vector<int> v;
void factorizeaza(int n)
{
if(n%2==0)
{
v.push_back(2);
do
{
n/=2;
}
while(n%2==0);
}
for(int i=3; n>1; i+=2)
if(n%i==0)
{
v.push_back(i);
do
{
n/=i;
}
while(n%i==0);
}
}
long long phi(long long x)
{
for(unsigned int i=0;i<v.size();++i)
{
x/=v[i];
x*=v[i]-1;
}
return x;
}
long long PrimN(long long x)
{
long long solutie=0;
for(int i=0;i<(1<<v.size());++i)
{
long long prod=1,semn=1;
for(int j=0;j<v.size();++j)
if(i&(1<<j))
{
prod*=v[j];
semn*=-1;
}
solutie+=x/prod*semn;
}
return solutie;
}
long long cautbin(long long x)
{
long long st=0,dr=N-1,LastApp=-1;
while(st<=dr)
{
long long mij=(dr-st)/2+st;
long long Intermediate=PrimN(mij);
if(Intermediate<P) {st=mij+1;continue;}
if(Intermediate>P) {dr=mij-1;continue;}
LastApp=mij;
dr=mij-1;
}
return LastApp;
}
int main()
{
ifstream f("frac.in");
ofstream g("frac.out");
f>>N>>P;
factorizeaza(N);
long long OrdN=phi(N);
long long Interval;
if(P%OrdN==0)
{g<<N*P/OrdN-1<<'\n';return 0;}
Interval=P/OrdN;
P%=OrdN;
long long rez=cautbin(P);
g<<Interval*N+rez<<'\n';
return 0;
}