Go: package main

import (
	"fmt"
	"math"
)

func main() {
	var n int
	fmt.Scan(&n)
	for i := 0; i < n; i++ {
		var xa, ya, ra, xb, yb, rb float64
		fmt.Scan(&xa, &ya, &ra, &xb, &yb, &rb)
		// println(xa, ya, ra, xb, yb, rb)
		dis := math.Sqrt((xa-xb)*(xa-xb) + (ya-yb)*(ya-yb))
		if dis + ra < rb {
			fmt.Println(-2)
		} else if dis + rb < ra {
			fmt.Println(2)
		} else if dis > rb + ra {
			fmt.Println(0)
		} else {
			fmt.Println(1)
		}
	}
}

C++: #include <cstdio>
#include <cmath>
#include <cstring>
#include <cstdlib>
#include <climits>
#include <ctime>
#include <queue>
#include <stack>
#include <algorithm>
#include <list>
#include <vector>
#include <set>
#include <map>
#include <iostream>
#include <deque>
#include <complex>
#include <string>
#include <iomanip>
#include <sstream>
#include <bitset>
#include <valarray>
#include <iterator>
using namespace std;
typedef long long int ll;
typedef unsigned int uint;
typedef unsigned char uchar;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;

#define REP(i,x) for(int i=0;i<(int)(x);i++)
#define FOR(i,c) for(__typeof((c).begin())i=(c).begin();i!=(c).end();i++)
#define RREP(i,x) for(int i=((int)(x)-1);i>=0;i--)
#define RFOR(i,c) for(__typeof((c).rbegin())i=(c).rbegin();i!=(c).rend();i++)
#define ALL(container) container.begin(), container.end()
#define RALL(container) container.rbegin(), container.rend()
#define SZ(container) ((int)container.size())
#define mp(a,b) make_pair(a, b)
#define UNIQUE(v) v.erase( unique(v.begin(), v.end()), v.end() );

template<class T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }
template<class T> ostream& operator<<(ostream &os, const vector<T> &t) {
os<<"["; FOR(it,t) {if(it!=t.begin()) os<<","; os<<*it;} os<<"]"; return os;
}
template<class T> ostream& operator<<(ostream &os, const set<T> &t) {
os<<"{"; FOR(it,t) {if(it!=t.begin()) os<<","; os<<*it;} os<<"}"; return os;
}
template<class S, class T> ostream& operator<<(ostream &os, const pair<S,T> &t) { return os<<"("<<t.first<<","<<t.second<<")";}
template<class S, class T> pair<S,T> operator+(const pair<S,T> &s, const pair<S,T> &t){ return pair<S,T>(s.first+t.first, s.second+t.second);}
template<class S, class T> pair<S,T> operator-(const pair<S,T> &s, const pair<S,T> &t){ return pair<S,T>(s.first-t.first, s.second-t.second);}

const int INF = 1<<28;
const double EPS = 1e-8;
const int MOD = 1000000007;

namespace geom{
#define X real()
#define Y imag()
	
	typedef double R;
	typedef complex<R> P;
	istream& operator>>(istream &is, P &p) {
		double x, y;
		is >> x >> y;
		p = P(x, y);
		return is;
	}
	struct L : public vector<P>{
		L(const P &p1, const P &p2){this->push_back(p1);this->push_back(p2);}
		friend istream& operator>>(istream &is, L &l) {
			P p1, p2;
			is >> p1 >> p2;
			l = L(p1, p2);
			return is;
		}
	};
	inline int sig(double x) { return (abs(x) < EPS ? 0 : x > 0 ? 1 : -1); }
	inline R norm(const P &p){return p.X*p.X+p.Y*p.Y;}
	inline R inp(const P& a, const P& b){return (conj(a)*b).X;}
	inline R outp(const P& a, const P& b){return (conj(a)*b).Y;}
	inline P unit(const P& p){return p/abs(p);}
	inline P proj(const P &s, const P &t){return t*inp(s, t)/norm(t);}
	inline P proj(const P &s, const L &t){return t[0] + proj(s-t[0], t[1]-t[0]);}
	inline bool sp_intersect(const L &s, const P &p){return !sig(abs(s[0]-p) + abs(s[1] - p) - abs(s[0] - s[1]));}
	
	struct C : public P{
		double r;
		friend istream& operator>>(istream &is, C &c) {
			operator>>(is, (P &)c);
			is >> c.r;
			return is;
		}
	};
	
	struct G : public vector<P>{
		enum {OUT, IN, ON};
		P &at(int i){return (*this)[i];}
		bool contains(const P &p){
			R sum = .0;
			REP(i, size()){
				if(sp_intersect(L(at(i), at((i+1)%size())), p)) return ON;	// online
				sum += arg((at(i) - p) / (at((i+1)%size()) - p));
			}
			return sig(sum) ? IN : OUT;
		}
		
		R area(){
			R sum = 0;
			REP(i, size()) sum += outp(at(i), at((i+1)%size()));
			return abs(sum / 2.);
		}
	};
};
using namespace geom;

int n;

int main(){
	ios::sync_with_stdio(false);
	int T;
	cin >> T;
	REP(t, T){
		C a, b;
		cin >> a >> b;
		int ans;
		if(abs(a-b) > a.r + a.r) ans = 0;
		else if(abs(a-b)+b.r < a.r) ans = 2;
		else if(abs(a-b)+a.r < b.r) ans = -2;
		else ans = 1;
		cout << ans << endl;
	}
	return 0;
}

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

int main()
{
	int n;
	cin >> n;
	while (n--)
	{
		double Xa, Ya, Ra, Xb, Yb, Rb;
		cin >> Xa >> Ya >> Ra >> Xb >> Yb >> Rb;

		double distance = sqrt(pow(Xb - Xa, 2) + pow(Yb - Ya, 2));
		if (distance > Ra + Rb)
		{
			cout << 0 << endl;
			continue;
		}
		if (distance + Rb < Ra)
		{
			cout << 2 << endl;
			continue;
		}
		if (distance + Ra < Rb)
		{
			cout << -2 << endl;
			continue;
		}
		cout << 1 << endl;
	}

	return 0;
}

C++: #include <iostream>
#include <string>
#include <vector>
#include <cmath>
using namespace std;

int main() {
    int n;
    cin >> n;
    double xa, ya, ra, xb, yb, rb;
    while (n--) {
        cin >> xa >> ya >> ra >> xb >> yb >> rb;
        double d = sqrt((xb - xa) * (xb - xa) + (yb - ya) * (yb - ya));
        if (ra + rb < d + 1e-9) {
            cout << 0 << endl;
        } else if (d + ra < rb + 1e-9) {
            cout << -2 << endl;
        } else if (d + rb < ra + 1e-9) {
            cout << 2 << endl;
        } else {
            cout << 1 << endl;
        }
    }
    return 0;
}

C++: #include<stdio.h>
#include<math.h>
#include<stdlib.h>

int main()
{
	int n, i;
	double xa, ya, ra, xb, yb, rb;
	scanf("%d", &n);
	for (i = 0; i < n; i++)
	{
		scanf("%lf %lf %lf %lf %lf %lf", &xa, &ya, &ra, &xb, &yb, &rb);
		double lr = ra>rb ? ra : rb,
			sr = ra > rb ? rb : ra,
			distance = sqrt(pow(xa - xb, 2) + pow(ya - yb, 2));
		if (distance > ra + rb)
		{
			printf("0\n");
		}
		else if (distance < lr - sr)
		{
			if (lr == ra)printf("2\n");
			else printf("-2\n");
		}
		else
			printf("1\n");
	}
	return 0;
}

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

int main() {
	int T; cin >> T;
	for (int t = 1; t <= T;t++) {
		double xa, ya, ra, xb, yb, rb;
		cin >> xa >> ya >> ra >> xb >> yb >> rb;

		double dist = pow(xa - xb, 2) + pow(xb - yb, 2);
		if (pow(ra + rb, 2) < dist) {
			cout << 0 << endl;
		}
		else {
			if (dist == 0 && ra == rb) {
				cout << 1 << endl;
			}
			else if (dist < pow(ra - rb, 2) && rb < ra) {
				cout << 2 << endl;
			}
			else {
				cout << -2 << endl;
			}
		}
	}
}

C++: #include <iostream>
#include <array>
#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;
}

C++: #include <cstdio>
#include <cmath>
#include <iostream>
using namespace std;

int main(int argc, char *argv[]) {
	int dataN;
	scanf("%d", &dataN);
	for (int i = 0; i < dataN; i++) {
		float ax, ay, ra, bx, by, rb;
		scanf("%f %f %f %f %f %f", &ax, &ay, &ra, &bx, &by, &rb);
		double d = (ax-bx)*(ax-bx) + (ay-by)*(ay-by);

		d = sqrt(d);

		if (ra > rb && ra >= d + rb) {
		  cout<<2<<endl;
		} else if (rb > ra && rb >= d + ra) {
		  cout<<-2<<endl;
		} else if (ra + rb < d) {
		  cout<<0<<endl;
		} else {
		  cout<<1<<endl;
		}
	}
	return 0;
}