[Java] HackerRank_Java If-Else와 Loops

 

1. Java If-Else

[Problem]

In this challenge, we test your knowledge of using if-else conditional statements to automate decision-making processes. An if-else statement has the following logical flow:

Source: Wikipedia

Task
Given an integer, n, perform the following conditional actions:

• If n is odd, print Weird
• If n is even and in the inclusive range of 2 to 5, print Not Weird
• If n is even and in the inclusive range of 6 to 20, print Weird
• If n is even and greater than 20, print Not Weird

Complete the stub code provided in your editor to print whether or not n is weird.

Input Format

A single line containing a positive integer, n.

Constraints

• 1 ≤ n ≤ 100

Output Format

Print Weird if the number is weird; otherwise, print Not Weird.

Sample Input 0

3

Sample Output 0

Weird

Sample Input 1

24

Sample Output 1

Not Weird

Explanation

Sample Case 0: n = 3
n is odd and odd numbers are weird, so we print Weird.

Sample Case 1: n = 24
n > 20 and n is even, so it isn't weird. Thus, we print Not Weird.

 

[Solution]

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class Solution {

    private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) {
        int N = scanner.nextInt();
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");
        if ( N % 2 == 1 ) { // N is odd
            System.out.println("Weird");
        } else { // N is even
            if ( N >= 2 && N <= 5 ) {
                System.out.println("Not Weird");
            } else if ( N >= 6 && N <= 20 ) {
                System.out.println("Weird");
            } else {
                System.out.println("Not Weird");
            }
        }
        scanner.close();
    }
}

2. Java Loops

[Problem]

Objective
In this challenge, we're going to use loops to help us do some simple math.

Task
Given an integer, N, print its first 10 multiples. Each multiple N × i (where 1 ≤ i ≤ 10) should be printed on a new line in the form: N x i = result.

Input Format

A single integer, N.

Constraints

• 2 ≤ N ≤ 20

Output Format

Print 10 lines of output; each line i (where 1 ≤ i ≤ 10) contains the result of N × i in the form:
N x i = result.

Sample Input

2

Sample Output

2 x 1 = 2

2 x 2 = 4

2 x 3 = 6

2 x 4 = 8

2 x 5 = 10

2 x 6 = 12

2 x 7 = 14

2 x 8 = 16

2 x 9 = 18

2 x 10 = 20

[Solution]

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class Solution {

    private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) {
        int N = scanner.nextInt();
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");
        for ( int i = 1; i <= 10; ++i ) {
            System.out.println(String.format("%d x %d = %d", N, i, N * i));
        }
        scanner.close();
    }
}