Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	for scanner.Scan() {
		strNums := strings.Fields(scanner.Text())
		nums := []int{}
		for _, strNum := range strNums {
			num, _ := strconv.Atoi(strNum)
			nums = append(nums, num)
		}
		a := nums[0]
		b := nums[1]
		c := nums[2]
		d := nums[3]
		e := nums[4]
		f := nums[5]
		var mulA, mulD int
		if a < 0 {
			mulA = a * -1
		} else {
			mulA = a
		}
		if d < 0 {
			mulD = d * -1
		} else {
			mulD = d
		}
		a *= mulD
		b *= mulD
		c *= mulD
		d *= mulA
		e *= mulA
		f *= mulA

		if d < 0 {
			d *= -1
			e *= -1
			f *= -1
		}

		bE := b - e
		cF := c - f
		if bE == 0 {
			bE = 1
		}
		y := cF / bE
		x := (c - (y * b)) / a

		fmt.Printf("%d.000 ", x)
		fmt.Printf("%d.000\n", y)
	}
}

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


int main(void){

  int a;
  int b;
  int c;
  int d;
  int e;
  int f;

  float x;
  float y;

  cin >> a >> b >> c >> d >> e >> f;

  x = a * e - b * d ;
  y = b * d - a * e ;

  if ((x == 0) && (y == 0)){
    cerr << "x?????????y??????????????????" << endl;
    exit(1);
  }else if(x == 0){
    cerr << "x??????????????????" << endl;
    exit(1);
  }else if(y == 0){
    cerr << "y??????????????????" << endl;
    exit(1);
  }else{

    if(c * e - b * f == 0){
      x = 0;
    }else{
      x = ( c * e - b * f ) / x ;
    }

    if(c * d - a * f == 0){
      y = 0;
    }else{
      y = ( c * d - a * f) / y;
    }
    
    cout << fixed << setprecision(3) << x << "   " << fixed << setprecision(3) << y << endl;
  }

  return 0;


}

C++: #include <iostream>
#include <sstream>
#include <string>
#include <algorithm>
#include <cstdlib>
#include <vector>
#include <iomanip>
#include <queue>
#include <cmath>
using namespace std;


int GetDigit(int n){
	int i = 0;

	while(n > 0){
		n /= 10;
		i++;
	}

	return i;
}
 
int main(){
	double a, b, c, d, e, f;
	double x, y;

	cout.flags(ios::fixed);
	cout.precision(3);
	
	while(cin >> a >> b >> c >> d >> e >> f){
		x = (c*e-b*f)/(a*e-b*d);
		y = (c*d-a*f)/(b*d-a*e);

		if(x == -0.0) x = abs(x);
		if(y == -0.0) y = abs(y);
		cout << x << ' ' << y << endl;
	}

	return 0;
}

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

main(){
  
  double a,b,c,d,e,f;
  double x, y;
  

  while(cin >> a >> b >> c >> d >> e >> f){
  

    y = (c*d - f*a)/(b*d-e*a);
    x = (b*y - c)/a;
    
    
    x*=10000;
    y*=10000;
    
    x+=0.5;
    y+=0.5;
    
    x/=10000;
    y/=10000;
    
    //cout << x << y << endl;
    printf("%.3f %.3f\n", x, y);
  }

  return 0;
}

C++: #include <iostream>
#include <vector>
#include <sstream>
#include <iomanip>

using namespace std;

vector<string> split(const string &s, char delim) {
    vector<string> elems;
    stringstream ss(s);
    string item;
    while (getline(ss, item, delim)) {
        if (!item.empty()) {
            elems.push_back(item);
        }
    }
    return elems;
}

double calc_y(double a, double b, double c, double d, double e, double f) {
    double y = (((d * c) / a) - f ) / (((d * b) / a) - e );
    return y;
}

int main() {
    string str;
    while(getline(cin, str)) {
        vector<string> splited = split(str, ' ');
        double a = stod(splited[0].c_str());
        double b = stod(splited[1].c_str());
        double c = stod(splited[2].c_str());
        double d = stod(splited[3].c_str());
        double e = stod(splited[4].c_str());
        double f = stod(splited[5].c_str());
        double y = calc_y(a, b, c, d, e, f);
        double x = (c - (b * y)) / a;
        cout <<  fixed << setprecision(3) << x << " " << fixed << setprecision(3)  << y << endl;
    }

    return 0;
}

C++: #include <bits/stdc++.h>
#define rep(i,j,k) for(int i=(int)j;i<(int)k;i++)
#define itrep(i,x) for(auto i=(x).begin(); i!=(x).end();i++)
#define Sort(x) sort((x).begin(),(x).end())
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define vi vector<int>
#define INF (int)1e9
#define INFL 1e18
#define MOD 1000000007
#define pb push_back
#define MP make_pair
#define PI 3.1415926535
typedef long long int ll;
typedef std::pair<int,int> P;
int D=1;
int dx[4]={0,1,0,-1},dy[4]={-1,0,1,0};

using namespace std;

double se(double x){
    x*=10000.0;
    if((int)x%10>=5){
        x+=10.0;
    }
    x/=10000.0;
    
    return x;
}

int main(){
    double a,b,c,d,e,f;
    while(cin>>a>>b>>c>>d>>e>>f){
        printf("%.3f",se((c*e-f*b)/(a*e-b*d)));
        cout<<" ";
        printf("%.3f",se((a*f-c*d)/(a*e-b*d)));
        cout<<endl;
    }
    
    return 0;
}

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


int main(){
    
	double a, b, c, d, e, f;
    double x, y;
    
	while(cin>> a>> b>> c >> d>> e>> f){
        
        x = 0.0;
        y = 0.0;
        
                
        y = (c*d-f*a)/(b*d-a*e);
        
        x = (c*e-f*a)/(a*e-b*d);

        if (x == 0) {
            x = 0;
        }
        else if (y == 0) {
            y = 0;
        }
        
        printf("%.3f %.3f\n", x, y);
        
        
	}
    
    
	return 0;
}

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

int main(){
	double a, b, c, d, e, f, x, y;
	
	while(std::cin>>a>>b>>c>>d>>e>>f){
	
		y = (d*c-a*f) / (b*d-a*e); // 連立方程式のyの解
		x = (c-b*y) / a; // xの解
		
		std::cout << std::fixed << std::setprecision(3) << x << " " << y << "\n"; // 桁数の調整
	}
	return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <cmath>
using namespace std; 
int main()
{
double a,b,c,d,e,f;
while(cin>>a>>b>>c>>d>>e>>f)
{
printf("%.3f %.3f\n", round((1.0 * b*f - c*e)/(b*d - a*e) * 1000) / 1000, round((1.0 * a*f - c*d)/(a*e - b*d) * 1000) / 1000);
}
return 0;
}

C++: #include<cstdio>
#include<algorithm>
#include<cmath>

using namespace std;

int main(){
        double a, b, c, d, e, f, g, h, i, j, k, l, m, n, x, y;

        while(scanf("%lf%lf%lf%lf%lf%lf", &a, &b, &c, &d, &e, &f) != EOF){
                g = a * d;      //公倍数
                j = b;
                k = c;
                l = a;
                b *= g / a;
                c *= g / a;
                e *= g / d;
                f *= g / d;
                a *= g / a;
                d *= g / d;

                h = b - e;
                i = c - f;

                y = i / h;
                x = k - y * j;
                x /= l;
                y *= 1000;
                y = floor(y + 0.5);
                y /= 1000;
                x *= 1000;
                x = floor(x + 0.5);
                x /= 1000;

                printf("%.%df %.3f\n", x, y);
        }

        return 0;
}

C++: #include<iostream>
using namespace std;
int main(){
	double a[60000000]={0};
	int i=0;
	while(cin>>a[i++]);
	int n=i-1;
	for(int j=0;j<n;j+=6){
		double k=a[j]/a[j+3],x=0,y=0;
		a[j+3]*=k,a[j+4]*=k,a[j+5]*=k;
		y=(a[j+2]-a[j+5])/(a[j+1]-a[j+4]);
		x=(a[j+2]-a[j+1]*y)/a[j];
		cout<<x<<" "<<y<<endl;
	}
	return 0;
}

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

int main(){
  while(cin){
    double A[2][3];
    for(int i=0;i<2;i++){
      for(int j=0;j<3;j++){
	cin>>A[i][j];
      }
    }
    for(int i=0;i<2;i++){
      for(int j=i+1;j<3;j++){
	A[i][j] /= A[i][i];
      }
      for(int k=0;k<2;k++){
	if(k!=i){
	  
	  for(int j=i+1;j<3;j++) A[k][j] -= A[k][i]*A[i][j];
	}
      }
    }
    cout<<fixed<<setprecision(3)<<A[0][2]<<" "<<A[1][2]<<endl;
  }
  return 0;
}

C++: #include<iostream>
#include<stdio.h>
using namespace std;
int main(){
 double a,b,c,d,e,f,y[10000],x[10000];
 int i=0,n;
while(scanf("%lf%lf%lf%lf%lf%lf",&a,&b,&c,&d,&e,&f) != EOF){
  y[i]=((c*d)-(a*f))/((b*d)-(a*e));
  x[i]=((c*e)-(b*f))/((a*e)-(b*d));
  i++;
}
  n=i;
  for(i=0;i < n; i++){
  if(x == 0){x = 0;}
  if(y == 0){y = 0;}
  printf("%.3lf %.3lf\n", x[i],y[i]);
  }
  return 0;
}