import java.util.ArrayList;
import java.util.Scanner;

class Coordinate {
    double x = 0.0;
    double y = 0.0;
}

public class Main {
    public static void main(String[] args) {
        int caseNum = 0;
        int stationNum = 0;
        ArrayList<ArrayList<Coordinate>> testCaseList = new ArrayList<ArrayList<Coordinate>>();
        Scanner scan = new Scanner(System.in);

        caseNum = scan.nextInt();

        for (int i = 0; i < caseNum; i++) {
            ArrayList<Coordinate> stationList = new ArrayList<Coordinate>();

            stationNum = scan.nextInt();

            for (int j = 0; j < stationNum; j++) {
                Coordinate coo = new Coordinate();

                coo.x = scan.nextDouble();
                coo.y = scan.nextDouble();
                stationList.add(coo);
            }

            testCaseList.add(stationList);
        }

        for (ArrayList<Coordinate> stationList : testCaseList) {
            ArrayList<Double> closeDistanceList = new ArrayList<Double>();
            double minimumPower = 0.0;

            for (int standard = 0; standard < (stationList.size() - 1); standard++) {
                double closeDistance = 2000000.0;

                for (int comparison = standard + 1; comparison < stationList.size(); comparison++) {
                    double differenceX = stationList.get(standard).x - stationList.get(comparison).x;
                    double differenceY = stationList.get(standard).y - stationList.get(comparison).y;
                    double comparativeDistance = Math.pow(differenceX, 2) + Math.pow(differenceY, 2);

                    if (comparativeDistance < closeDistance) {
                        closeDistance = comparativeDistance;
                    }
                }

                closeDistanceList.add(closeDistance);
            }

            for (int i = 0; i < closeDistanceList.size(); i++) {
                if (minimumPower < closeDistanceList.get(i)) {
                    minimumPower = closeDistanceList.get(i);
                }
            }

            minimumPower = Math.round(Math.sqrt(minimumPower) * 100) / 100.0;

            System.out.println();
            System.out.printf("%.2f", minimumPower);
        }
    }
}