import java.io.FileInputStream;
import java.util.Scanner;

public class Main {

    static int testCase;
    static int N;
    static float centerPoint[][];
    static float distance[];
    static float distanceVia[][];
    static float visitPoint[][];
    static float minDistance[];
    static float Rst = 0;
    static int CP=0;
    static String output;


    public static float getDistance(float i, float j, float k, float l){
        float distance = 0;
        distance = (i - k)*(i - k) + (j-l)*(j-l); 
        return distance;
    }
    public static void main(String[] args) throws Exception{
        // TODO Auto-generated method stub

        Scanner sc = new Scanner(System.in);

        testCase = sc.nextInt();
        for( int i = 1 ; i <= testCase ; i++){
            N = sc.nextInt();
            centerPoint = new float[N][2];
            for(int j = 0 ; j < N ; j++)
            {
                centerPoint[j][0] = sc.nextFloat();
                centerPoint[j][1] = sc.nextFloat();
            }
            distance = new float[N*N];
            visitPoint = new float[N][N];
            distanceVia = new float[N][N];
            minDistance = new float[N];

            //알고리즘 구현
            //기준점에 대한 각 포인트 별 거리 구하기
            for(int j = 0 ; j < N ; j++){
                for(int k = 0 ; k < N ; k++){                   
                        distanceVia[j][k] = getDistance(centerPoint[j][0], centerPoint[j][1], 
                            centerPoint[k][0], centerPoint[k][1]);
                    }
                }


            for(int j = 0; j < N ; j++)
            {
                dfs(CP, -1);
                CP++;
                if(CP == N)
                {
                    CP = 0;
                    break;
                }
            }


            for(int j = 0 ; j < N ; j++){
                for(int k = 0 ; k < N ; k++){
                    if((visitPoint[j][k] > minDistance[j] ) && visitPoint[j][k]!= 0 && visitPoint[j][k]!= -1){
                        minDistance[j] = visitPoint[j][k];  
                    }
                }               
            }

            for(int j = 0 ; j < N ; j++){
                if(Rst == 0 || Rst > minDistance[j]){
                    Rst = minDistance[j];
                }
            }
            output = String.format("%.2f", Math.sqrt(Rst));
            Rst = 0;
            System.out.println(output);
        }       
    }

    static void dfs(int start, float minVal){


        float minValue = -1;
        int p = 0;

        visitPoint[CP][start] = minVal;

        for(int i = 0 ; i < N; i++){
            if((  minValue == -1 || minValue > distanceVia[start][i] ) && distanceVia[start][i] != 0){      
                if( visitPoint[CP][i]!=0 ){
                    continue;
                }
                minValue = distanceVia[start][i];
                p = i;

            }

        }


        for(int i = 0 ; i < N ; i++){
            if( visitPoint[CP][i] == 0 ){
                dfs(p, minValue);
            }
        }
    }
}