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

double dis(double x1,double x2,double y1,double y2)
{
	
	return sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
}
int main()
{
	double x1,x2,x3,y1,y2,y3,c;
	cin>>x1>>x2>>x3>>y1>>y2>>y3;
	double dis1=dis(x1,x2,y1,y2),dis2=dis(x2,x3,y2,y3),dis3=dis(x1,x3,y1,y3);
	c = dis1 + dis2 + dis3;
	sprintf("%.2f",c)
	return 0;
}
```cpp