#include <queue>#include <stack>#include <math.h>#include <stdio.h>#include <stdlib.h>#include <iostream>#include <limits.h>#include <string.h>#include <algorithm>using namespace std;const int MAX = 1010;const double eps = 1e-10;const double pi = acos(-1.0);typedef struct Point{double x,y;}Point;Point c[MAX];bool dy(double x,double y) {return x > y + eps;}bool xy(double x,double y) {return x < y - eps;}bool dyd(double x,double y) {return x > y - eps;}bool xyd(double x,double y) {return x < y + eps;}bool dd(double x,double y) {return fabs( x - y ) < eps;}double crossProduct(Point a,Point b,Point c){return (c.x - a.x)*(b.y - a.y) - (b.x - a.x)*(c.y - a.y);}double Distance(Point a,Point b) {return sqrt( ( a.x - b.x ) * ( a.x - b.x ) + ( a.y - b.y ) * ( a.y - b.y ) );}bool cmp(Point a,Point b) {if( dd(a.y ,b.y ) )return xy(a.x, b.x);return xy(a.y,b.y);}bool cmp1(Point a,Point b) {double len = crossProduct(c[0],a,b);if( dd(len,0.0) )return xy(Distance(c[0],a),Distance(c[0],b));return xy(len,0.0);}double circum(double r){return 2 * pi * r;}Point stk[MAX];int top;double dis(){double sum = 0.0;for(int i=0; i<top; i++)sum += Distance(stk[i],stk[i+1]);sum += Distance(stk[0],stk[top]);return sum;}double Graham(int n){sort(c,c+n,cmp);sort(c+1,c+n,cmp1);top = 0;stk[top++] = c[0];stk[top++] = c[1];stk[top++] = c[2];top--;for(int i=3; i<n; i++){while(1){Point a,b;a = stk[top];b = stk[top-1];if( xyd( crossProduct(a,b,c[i]), 0.0 ) )top--;elsebreak;}stk[++top] = c[i];}return dis();}int main(){int ncases;int n,l;scanf("%d",&ncases);while( ncases-- ){scanf("%d %d",&n,&l);for(int i=0; i<n; i++)scanf("%lf %lf",&c[i].x,&c[i].y);double ans = Graham(n);double len = circum(l);printf("%.0lfn",(ans+len));if( ncases )printf("n");} return 0;}
