#include <iostream>
#include <fstream>
using namespace std;
//fara pinex
//O(c*d)
ifstream f("mins.in");
ofstream g("mins.out");
const int MAX=5001;

int ln,cl;
long long sol;
bool a[MAX][MAX];

void read()
{
    f>>ln>>cl;
    ln--;cl--;
}
void solve()
{
    int x,y,i,j;
    sol=ln*cl;
    for(x=1;x<=ln;x++)
        for(y=1;y<=cl;y++)
            if(!a[x][y])
                {
                    a[x][y]=1;
                    for(i=2*x,j=2*y;i<=ln && j<=cl;i+=x, j+=y)
                    {a[i][j]=1;sol--;}
                }
    g<<sol;
}

int main()
{
    read();
    solve();
    return 0;
}