Recently I’ve been going through the HackerRank.com 30 Days of Code course to learn Java. Below is my code for their Day 1 lesson.
After reviewing the code I think I would prefer to add some data type checking to ensure that the data accepted from scan.nextLine() is actually the data type that I expect. It passed the unit tests provided by HackerRank but I doubt this would pass negative testing in a Test Driven Development organization.
import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;
public class Solution {
public static void main(String[] args) {
int i = 4;
double d = 4.0;
String s = "HackerRank ";
Scanner scan = new Scanner(System.in);
/* Declare second integer, double, and String variables. */
int j;
double e;
String t;
/* Read and save an integer, double, and String to your variables.*/
j = Integer.parseInt(scan.nextLine());
e = Double.parseDouble(scan.nextLine());
t = scan.nextLine();
/* Print the sum of both integer variables on a new line. */
System.out.println(i + j);
/* Print the sum of the double variables on a new line. */
System.out.println(d + e);
/* Concatenate and print the String variables on a new line;
the 's' variable above should be printed first. */
System.out.println(s + t);
scan.close();
}
}