Go: package main

import (
        "fmt"
        "math"
)

func main() {
        var n int
        fmt.Scanf("%d", &n)
        for i := 0; i < n; i++ {
                var ax, ay, ar, bx, by, br float64
                fmt.Scanf("%f %f %f %f %f %f", &ax, &ay, &ar, &bx, &by, &br)

                d := math.Sqrt((bx-ax)*(bx-ax) + (by-ay)*(by-ay))
                if d <= ar + br {
                        if ar > br {
                                if ar > br + d {
                                        fmt.Println("2")
                                } else {
                                        fmt.Println("1")
                                }
                        } else {
                                if br > ar + d {
                                        fmt.Println("-2")
                                } else {
                                        fmt.Println("1")
                                }
                        }
                } else {
                        fmt.Println(0)
                }
        }
}

C++: #include <cstdio>
#include <complex>
#include <vector>
#include <cmath>

using namespace std;

#define REP(i, n) for(int i = 0;i < n;i++)
#define REPR(i, n) for(int i = n;i >= 0;i--)
#define FOR(i, m, n) for(int i = m;i < n;i++)

typedef complex<double> P;
typedef vector<P> VP;
const double EPF = 1e-2;

#define X real()
#define Y imag()
#define EQ(x,y) (abs(x-y) < EPF)
#define LE(x,y) (x < y + EPF)
#define GE(x,y) (x + EPF > y)

double dot(P a, P b) {
  return (conj(a)*b).X;
}
double cross(P a, P b) {
  return (conj(a)*b).Y;
}
int isparallel(P a, P b, P c, P d) {//ab,cd
  return EQ(cross(a-b, c-d),0);
}
double distPP(P a, P b) {
  return sqrt(dot(a-b,a-b));
}
int relationCC(P c1, double r1, P c2, double r2) {//0..not overlap, 1..intersect, 2..2isin1, -2..1isin2
  double d = distPP(c1,c2);
  if(GE(d , r1+r2)) return 0;
  else if(GE(d , r1-r2) && GE(d , r2-r1)) return 1;
  else if(GE(r1 , r2)) return 2;
  else return -2;
  return -1;
}
P intersection(P a, P b, P c, P d) {//ac , bd
  double d1 = cross(d-b,b-a);
  double d2 = cross(d-b,c-a);
  if(EQ(d1,0) & EQ(d2,0)) return a;
  if(EQ(d2,0)) return a;
  return a + (c-a)*d1/d2;
}
P normal_vector(P a) {
  P b(-a.Y, a.X);
  return b;
}
P polar(double r, double theta) {
  P a(r*cos(theta),r*sin(theta));
  return a;
}


int main() {
  int n;
  scanf("%d",&n);
  REP(i,n) {
    double x,y,r1,r2;
    scanf("%lf %lf %lf", &x, &y, &r1);
    P a(x,y);
    scanf("%lf %lf %lf", &x, &y, &r2);
    P b(x,y);
    printf("%d\n", relationCC(a,r1,b,r2));
  }
  return 0;
}

C++: #include<iostream>
#include<cmath>

define 

int main(){
  int n;
  double xa,ya,ra,xb,yb,rb,d;
  std::cin >> n;

  for(int i=0;i<n;i++){
    std::cin >> xa >> ya >> ra
             >> xb >> yb >> rb;
    d = std::sqrt((xa-xb)*(xa-xb)+(ya-yb)*(ya-yb));
    if(ra+rb <= d){
      std::cout << 0 << std::endl;
      break;
    }
    if(ra+d <= rb){
      std::cout << -2 << std::endl;
      break;
    }
    if(rb+d <= ra){
      std::cout << 2 << std::endl;
    }else{
      std::cout << 1 << std::endl;
    }
  }
}

C++: #include <cstdio>
#include <complex>
#include <vector>
#include <cmath>

using namespace std;

#define REP(i, n) for(int i = 0;i < n;i++)
#define REPR(i, n) for(int i = n;i >= 0;i--)
#define FOR(i, m, n) for(int i = m;i < n;i++)

typedef complex<double> P;
typedef vector<P> VP;
const double EPF = 1e-2;

#define X real()
#define Y imag()
#define EQ(x,y) (abs(x-y) < EPF)
#define LE(x,y) (x < y + EPF)
#define GE(x,y) (x + EPF > y)

double dot(P a, P b) {
  return (conj(a)*b).X;
}
double cross(P a, P b) {
  return (conj(a)*b).Y;
}
int isparallel(P a, P b, P c, P d) {//ab,cd
  return EQ(cross(a-b, c-d),0);
}
double distPP(P a, P b) {
  return sqrt(dot(a-b,a-b));
}
int relationCC(P c1, double r1, P c2, double r2) {//0..not overlap, 1..intersect, 2..2isin1, -2..1isin2
  double d = distPP(c1,c2);
  if(d > r1+r2) return 0;
  else if(r1 > d+r2) return 2;
  else if(r2 > d+r1) return -2;
  else return 1;
}
P intersection(P a, P b, P c, P d) {//ac , bd
  double d1 = cross(d-b,b-a);
  double d2 = cross(d-b,c-a);
  if(EQ(d1,0) & EQ(d2,0)) return a;
  if(EQ(d2,0)) return a;
  return a + (c-a)*d1/d2;
}
P normal_vector(P a) {
  P b(-a.Y, a.X);
  return b;
}
P polar(double r, double theta) {
  P a(r*cos(theta),r*sin(theta));
  return a;
}


int main() {
  int n;
  scanf("%d",&n);
  REP(i,n) {
    double x,y,r1,r2;
    scanf("%lf %lf %lf", &x, &y, &r1);
    P a(x,y);
    scanf("%lf %lf %lf", &x, &y, &r2);
    P b(x,y);
    printf("%d\n", relationCC(a,r1,b,r2));
  }
  return 0;
}

C++: #include<iostream>
#include<math.h>
using namespace std;

int checker(int i,double* x1,double* y1,double* r1,double* x2,double*y2,double* r2){
  double x=x1[i]-x2[i];
  double y=y1[i]-y2[i];
  if(r1[i]>r2[i]){
    if(sqrt(x*x+y*y)<r1[i]-r2[i])return 2;
    else if(sqrt(x*x+y*y)>=r1[i]-r2[i]&&sqrt(x*x+y*y)<=r1[i]+r2[i])return 1;
    else if(sqrt(x*x+y*y)>r1[i]+r2[i])return 0;
  }
  else {
    if(sqrt(x*x+y*y)<r2[i]-r1[i])return -2;
    else if(sqrt(x*x+y*y)>=r2[i]-r1[i]&&sqrt(x*x+y*y)<=r1[i]+r2[i])return 1;
    else if(sqrt(x*x+y*y)>r1[i]+r2[i])return 0;
  }
}
int main(){
  int x;
  cin>>x;
  int answers[x];double x1[x],y1[x],r1[x],x2[x],y2[x],r2[x];
  for(int i=0;i<x;i++){
    cin>>x1[i]>>y1[i]>>r1[i]>>x2[i]>>y2[i]>>r2[i];
    answers[i]=checker(i,x1,y1,r1,x2,y2,r2);
  }
  for(int i=0;i<x;i++){
    cout<<answers[i]<<endl;
  }
}

C++: #include<iostream>
#include<string>
#include<cstdio>
#include<algorithm>
#include<stack>
#include<queue>
#include<vector>
#include<cmath>
#include<utility>
#define ll long long int
#define ld long long double
#define INF 1000000000
#define EPS 0.0000000001
#define rep(i,n) for(i=0;i<n;i++)
using namespace std;
typedef pair<int, int> P;

string str;

int main()
{
  int n,i;
  double xa,ya,ra,xb,yb,rb;
  double dist;

  cin>>n;
  rep(i,n){

    cin>>xa>>ya>>ra>>xb>>yb>>rb;
    dist=sqrt( (xa-xb)*(xa-xb)+(ya-yb)*(ya-yb) );

    if(dist>ra+rb)
      cout<<"0"<<endl;
    else if(ra<dist)
      cout<<"1"<<endl;
    else if(rb<ra)
      cout<<"2"<<endl;
    else if(ra<rb)
      cout<<"-2"<<endl;
  }
}

C++: #include <iostream>
#include <cmath>

int main(){
	
	int data;
	
	std::cin >> data;  //dataset
	
	std::array<double, data>xa;
	std::array<double, data>ya;
	std::array<double, data>ra;
	std::array<double, data>xb;
	std::array<double, data>yb;
	std::array<double, data>rb;
	
	for(int i=0; i<data; ++i){
		std::cin >> xa[i];
		std::cin >> ya[i];
		std::cin >> ra[i];
		std::cin >> xb[i];
		std::cin >> yb[i];
		std::cin >> rb[i];
	}
	
	double length;  //a-b length;
	
	length = hypot(abs(xa-xb),abs(ya-yb));
	
	if(length > ra+rb){
		std::cout << 0 << std::endl;
	}else if(length + rb < ra){
		std::cout << 2 << std::endl; 
	}else if(length + ra < rb){
		std::cout << -2 << std::endl; 
	}else{
		std::cout << 1 << std::endl; 
	}
	
	return 0;
}