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#include <fstream>
#include <vector>
using namespace std;
const int VMAX = 1e6;
int nrdp[1+VMAX], x, y;
long long rez;
vector <int> prime;
void calcul_nrdp(int n)
{
for (int i = 2; i <= n; i++)
{
if (nrdp[i] == 0)
{
if (i * i <= n)
{
prime.push_back(i);///voi marca multiplii lui i
}
for (int multiplu = i; multiplu <= n; multiplu += i)
{
nrdp[multiplu]++;
}
}
}
for (auto p: prime)
{
int patrat = p * p;
for (int multiplu = patrat; multiplu <= n; multiplu += patrat)
{
nrdp[multiplu] = -1;
}
}
}
int main()
{
ifstream in("mins.in");
ofstream out("mins.out");
in >> x >> y;
int n = min(x-1, y-1);
calcul_nrdp(n);
rez = (long long)(x- 1) * (y - 1);
for (int i = 2; i <= n; i++)
{
if (nrdp[i] != -1)
{
long long nr_fractii_red = ((long long)(x - 1) / i) * ((long long)(y - 1) / i);
if (nrdp[i] % 2 == 0)
{
rez += nr_fractii_red;
}
else
{
rez -= nr_fractii_red;
}
}
}
out << rez;
in.close();
out.close();
return 0;
}