RaceResults

import java.util.Arrays;
import java.util.Scanner;

public class RaceResults
{
  public static void main(String[] args)
  {
    Scanner sc = new Scanner(System.in);
    int runners = -1;

    do {
      System.out.print("Enter number of runners: ");
      if (sc.hasNextInt()) {
        runners = sc.nextInt();
      } else sc.next();
    }
    while (runners <= 0);    // Data validation for number of runners

    double[] times = new double[runners];

    int count = 0;
    System.out.println("Enter times for runners in seconds.");
    do {
      System.out.printf("Enter time for runner# %d: ", (count + 1));

      if (sc.hasNextDouble()) {
        times[count] = sc.nextDouble();
        count++;
      } else sc.next();
    }
    while (count < times.length);    //Data validation for the times of the runners

    for (int i = 0; i < times.length; i++) {
      System.out.printf("\nRunner # %d time: %.3f", (i +1), times[i]);
    }

    Arrays.sort(times);

    System.out.printf("\033[32m\nFastest time is: %.3f",times[0]);
    System.out.printf("\033[31m\nSlowest times is: %.3f",times[times.length - 1]);

    double sum = 0;
    for (double n: times){
      sum += n;
    }

    double avrg = sum/runners;   //calculating avrage time for all runners

    double[] mathArray = new double[times.length];          //new array to store calculated values from the first array

    for (int i = 0; i < times.length; i++) {
      mathArray[i] = Math.pow((times[i] - avrg), 2);        //substracting the avrage from each time and squaring the result and save
                                                            //it in the new array
    }

    double sum2 = 0;
    for (double n: mathArray){
      sum2 += n;
    }

    sum2 = Math.sqrt(sum2/runners);                 //calculating the the standart deviation by squaring the sum of the second
                                                    //array devided by the total number of runners

    System.out.printf("\033[39m\nStandard deviation is: %.3f ", sum2);
  }
}