#include <iostream>
#include<cmath>

using namespace std;

int main()
{
    double x1,y1,r1,x2,y2,r2;
    cin >>x1>>y1>>r1>>x2>>y2>>r2;
    double S=sqrt((x1-x2)*(x1+x2)+(y1-y2)*(y1+y2));
    if(r1>r2)
        swap(r1,r2);
    if((r1==r2)&&(x1==x2)&&(y1==y2));
    {
        cout<<-1<<endl;
        return 0;
    }
}