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 <algorithm>
#include <iostream>
#include <cstdio>
#include <map>
#include <numeric>
#include <cmath>
#include <set>
#include <sstream>
#include <string>
#include <vector>
#include <queue>
#include <string.h>
using namespace std;

#define ISEQ(c) (c).begin(), (c).end()
typedef long long ll;

int main() {
  int n;
  cin >> n;
  double x[2], y[2], r[2];
  const double EPS = 1e-9;
  for (int z = 0; z < n; z++) {
    cin >> x[0] >> y[0] >> r[0];
    cin >> x[1] >> y[1] >> r[1];
    double cdif = sqrt((x[0]-x[1])*(x[0]-x[1]) - (y[0]-y[1])*(y[0]-y[1]));
    if (cdif+r[0]-r[1] < EPS) cout << -2 << endl;
    else if (cdif+r[1]-r[0] < EPS) cout << 2 << endl;
    else if (cdif-r[0]-r[1] < EPS) cout << 1 << endl;
    else cout << 0 << endl;
  }
}

C++: #include <iostream>

using namespace std;

int main(int argc, char **argv)
{
	int n;
	float x1, y1, r1, x2, y2, r2, u;
	cin >> n;
	
	for(int i = 0; i < n; i++){
		cin >> x1 >> y1 >> r1 >> x2 >> y2 >> r2;
		u = (x1-x2)*(x1-x2) + (y1-y2)*(y1-y2);
		
		if(u+r2 < r1){
			cout << "2" << endl;
		} else if(u+r1 < r2){
			cout << "-2" << endl;
		} else if(r1+r2 <= u){
			cout << "1" << endl;
		} else {
			cout << "0" << endl;
		}
	}
	
	return 0;
}

C++: #include <iostream>
#include <cmath>
#define double long double
using namespace std;

int main()
{
	int n;
	double xa, ya, ra, xb, yb, rb;
	
	cin >> n;
	while(n--){
		cin >> xa >> ya >> ra >> xb >> yb >> rb;
		//B in A
		if( hypotl(xa - xb, ya - yb) + rb < ra )
			cout << 2 << endl;
		//A in B
		else if( hypotl(xa - xb, ya - yb) + ra < rb )
			cout << -2 << endl;
		//A intersect B
		else if( hypotl(xa - xb, ya - yb) <= ra + rb )
			cout << 1 << endl;
		else
			cout << 0 << endl;
	}
	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

#define iota(i,n,b,s) for(int i=int(b);i!=int((b)+(s)*(n));i+=(s))
#define range(i,n,m) iota(i,(((n)>(m))?((n)-(m)):((m)-(n))),(n),((n)>(m)?-1:1))
#define rep(i,n) iota(i,(n),0,1)
#define loop for(;;)

#define INF (1e9)
#define EPS (1e-9)
#define cons(a,b) (make_pair(a,b))
#define car(a) (a.first)
#define cdr(a) (a.second)
#define cadr(a) (car(cdr(a)))
#define cddr(a) (cdr(cdr(a)))
#define all(a) a.begin(), a.end()
#define trace(var) cerr<<">>> "<<#var<<" = "<<var<<endl;

typedef long long Integer;
typedef long double Real;
typedef vector<int> vi;
typedef vector<string> vs;
typedef map<string,int> Dictionary;
typedef pair<Real, Real> P; // Point
typedef pair<P, P> L; // segment or line
const Real PI = acos(-1);

template<class S, class T>
ostream& operator<<(ostream& os, pair<S,T> p) {
  os << '(' << car(p) << ", " << cdr(p) << ')';
  return os;
}
template<class T>
ostream& operator<<(ostream& os, vector<T> v) {
  os << v[0];
  for (int i=1, len=v.size(); i<len; ++i) os << ' ' << v[i];
  return os;
}

int dx[] = { -1, 0, 1, 0 };
int dy[] = {  0, -1, 0, 1 };

/* inner dot */
Real dot(P&a, P&b) {
  return car(a) * car(b) + cdr(a) * cdr(b);
}
Real operator*(P&a, P&b) {
  return car(a) * car(b) + cdr(a) * cdr(b);
}

/* scalar multiple */
P operator*(P a, Real c) {
  return cons(c * car(a), c * cdr(a));
}
P operator*(Real c, P a) {
  return cons(c * car(a), c * cdr(a));
}

P operator/(P a, Real d) {
  return cons(car(a) / d, cdr(a) / d);
}

Real det(P a, P b) {
  return car(a) * cdr(b) - cdr(a) * car(b);
}

/* vector operator */
P operator+(P a, P b) {
  return cons(car(a) + car(b), cdr(a) + cdr(b));
}

P operator-(P a) {
  return cons(-car(a), -cdr(a));
}

P operator-(P a, P b) {
  return cons(car(a) - car(b), cdr(a) - cdr(b));
}

/* distance */
Real Manhattan(P a, P b) {
  return abs(car(a) - car(b)) + abs(cdr(a) - cdr(b));
}
Real Euclidean(P a, P b) {
  P p = a - b;
  return sqrt(pow(car(p), 2) + pow(cdr(p), 2));
}

/* equality with EPS (default: 1e-9) */
bool eq(Real x, Real y) {
  return abs(x - y) < EPS;
}
bool operator==(P a, P b) {
  return eq(car(a), car(b)) && eq(cdr(a), cdr(b));
}

int sign(Real a) {
  if (eq(a, 0)) return 0;
  return a > 0 ? 1 : -1;
}

enum CCW {
  FRONT,
  BACK,
  RIGHT,
  LEFT,
  ON
};
CCW ccw(L&l, P&p) {
  P u = car(l);
  P v = cdr(l);

  P dif = p - u;
  P dir = v - u;

  if (eq(0, car(dir))) {
    if (eq(0, car(dif))) {
      Real k = cdr(dif) / cdr(dir);
      if (k > 1.0) return FRONT;
      if (k < 0.0) return BACK;
      return ON;
    } else {
      if (det(dir, dif) > 0.0) {
        return LEFT;
      }
      return RIGHT;
    }
  }

  Real k = car(dif) / car(dir);
  if (eq(cdr(dir) * k, cdr(dif))) {
    if (k > 1.0) return FRONT;
    if (k < 0.0) return BACK;
    return ON;
  } else {
    if (det(dir, dif) > 0.0) {
      return LEFT;
    }
    return RIGHT;
  }
}

Real magnitude(P&a) {
  return sqrt(pow(car(a), 2) + pow(cdr(a), 2));
}

Real arg(P&a, P&b) {
  Real x = dot(a, b) / magnitude(a) / magnitude(b);
  x = min<Real>(1, max<Real>(-1, x));
  return acos(x);
}

struct C {
  P o;
  Real r;
  C(P o, Real r) : o(o), r(r) {}
  C(Real x, Real y, Real r) : o(cons(x, y)), r(r) {}
};

enum circle_rel {
  SUB, SUP,
  TAN, INT,
  APT
};

circle_rel
circle_intersect(C a, C b) {
  Real d = Euclidean(a.o, b.o);
  //trace(cons(d, cons(a.r, b.r)));
  if (d + a.r < b.r) return SUB; // a is in b
  if (a.r > d + b.r) return SUP; // b is in a
  if (d < a.r + b.r) return INT;
  if (d <= a.r + b.r + EPS) return TAN;
  return APT;
}

int main() {
  int n; cin >> n;
  rep (_, n) {
    Real x1,y1,r1,
         x2,y2,r2;
    cin >> x1 >> y1 >> r1;
    cin >> x2 >> y2 >> r2;
    C c1(x1, y1, r1);
    C c2(x2, y2, r2);

    auto a = circle_intersect(c1, c2);
    cout << (a == SUB ? -2
           : a == SUP ? 2
           : a == APT ? 0 : 1) << endl;
  }
  return 0;
}

C++: #include <iostream>
#include <vector>
#include <list>
#include <algorithm>
#include <set>
#include <queue>
#include <stack>
#include <string>
#include <sstream>
#include <map>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>

#define rep(i, n) for(int i = 0; i < n; i ++)
#define COUNT(i, n) for(int i = 1; i <= n; i ++)
#define ITER(c) __typeof((c).begin())
#define each(c, it) for(ITER(c) it =(c).begin(); it!=(c).end(); it++)
#define ALL(c) c.begin(), c.end()
#define mp make_pair
#define pb push_back
#define MEMSET(v, h) memset((v), h, sizeof(v))
 
using namespace std; 

typedef pair<int, int> pii;
typedef long long ll;
typedef vector<int> vi;
typedef vector<string> vs;

const int INF = 1 << 24;

int main(void){
    int n; cin >> n;

    for(double xa, ya, ra, xb, yb, rb, d; n -- && cin >> xa >> ya >> ra >> xb >> yb >> rb; cout << (d > 0 ? 0:d < 0 ? ra < rb ? -2:ra > rb ? 2:1:1) << endl)
        d = sqrt(pow(xb - xa, 2) + pow(yb - ya, 2)) - (ra + rb);

    return 0;
}