#include<bits/stdc++.h>

using namespace std;
typedef long long LL;
LL gcd(LL a,LL b){
    return (b==0)?a:gcd(b,a%b);
}

int main(){
    LL a,b;
    cin>>a>>b;
    LL g=gcd(a,b);
    cout<<a/g-1<<endl;
    return 0;
}