#include <stdio.h>
#include<math.h>

	
	float distance(int n1,int m1,int n2,int m2){
		float d=0;float sum=0;
		d =sqrt(pow(m2-m1,2)+pow(n2-n1,2));
		sum+=d;
		printf("%.2f",sum);
		return sum;
	}
	int main(void) {
int t,n,i,j;float sum=0;
scanf("%d",&t);
while(t--){
	scanf("%d",&n);
	int r=0,s=0,a=0,b=0;
	int x[100002],y[100002],p[100002],q[100002],min[100002],max[100002];
	for(i=0;i<n;i++){
	scanf("%d %d",&x[i],&y[i]);}
	
	for(j=0;j<10001;j++){
		for(i=0;i<n;i++){
			if(j==x[i]){
				p[r++]=x[i];q[s++]=y[i];
			}
			}}
			for(i=0,j=i+1;i<n&&j<n;i++,j++){
				if(p[i]==p[j]){
					if(q[i]>q[j]){min[a++]=p[i]; max[b++]=q[i];}
					else{min[a++]=p[i]; max[b++]=q[j];}
				}
				else{min[a++]=p[i]; max[b++]=q[i];}
			}
	
	for(i=0;i<n;i++){
		distance(min[i],max[i],min[i+1],max[i+1]);
	}
	
	printf("%.2f\n",sum);
	
	
}

}