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#include <iostream>
#include <fstream>
#include <set>
#include <algorithm>
#include <limits.h>
#if 1
#define pv(x) cout<<#x<<" = "<<x<<"; ";cout.flush()
#define pn cout<<endl
#else
#define pv(x)
#define pn
#endif
using namespace std;
ifstream in("frac.in");
ofstream out("frac.out");
using ll = long long;
using ull = unsigned long long;
using ui = unsigned int;
#define pb push_back
#define mp make_pair
const int NMax = 5e6 + 5;
const int inf = 1e9 + 5;
const int mod = 100003;
using zint = int;
ll N,P;
ll primes[1000];
ll getPhi(ll N,ll B);
// getPhi(N,B) determina numarul de numere coprime cu B si mai mici sau egale cu N,
// ca la problema pinex din arhiva educationala;
int main() {
in>>N>>P;
// se realizeaza o cautare binara pe biti pentru
// numarul maxim nr care are getPhi(nr,N) mai mic ca P;
// raspunsul va fi primul numar unde se schimba valoarea functiei in P,
// adica nr+1;
ll pos = 0,pw = 1, lim = 1ull<<60;
for(;pw <= lim;pw <<= 1) ;
pw >>= 1;
while (pw) {
if (getPhi(pos+pw,N) < P) {
pos += pw;
}
pw >>= 1;
}
out<<pos+1<<'\n';
in.close();out.close();
return 0;
}
ll getPhi(ll N,ll B) {
ll nrPrimes = 0;
ll aux = B;
for (ll i=2;i*i <= aux;++i) {
if (aux % i != 0) {
continue;
}
while (aux % i == 0) {
aux /= i;
}
primes[++nrPrimes] = i;
}
if (aux != 1) {
primes[++nrPrimes] = aux;
}
ll lim = 1<<nrPrimes, total = 0;
for (ll mask = 1;mask < lim;++mask) {
ll prod = 1,nr = 0;
for (ll i=1;i <= nrPrimes;++i) {
if (((1<<(i-1)) & mask) != 0) {
prod *= primes[i];
++nr;
}
}
ll card = (nr % 2 == 1) ? N/prod : -N/prod;
total += card;
}
return N - total;
}