[2018.12.18] Staircase

Problem

Consider a staircase of size :

   #
  ##
 ###
####

Observe that its base and height are both equal to , and the image is drawn using # symbols and spaces. The last line is not preceded by any spaces.

Write a program that prints a staircase of size .

Function Description

Complete the staircase function in the editor below. It should print a staircase as described above.

staircase has the following parameter(s):

• n: an integer

Input Format

A single integer, , denoting the size of the staircase.

Constraints

 .

Output Format

Print a staircase of size  using # symbols and spaces.

Note: The last line must have  spaces in it.

Sample Input

6 

Sample Output

     #
    ##
   ###
  ####
 #####
######

Explanation

The staircase is right-aligned, composed of # symbols and spaces, and has a height and width of .

How I solved the problem

# 별그리기를 자주 했으면 볼 수 있는 문제

# 현재 층(index)보다 큰 범위가 들어갔을 때는 #이 들어가고 없으면 띄어쓰기가 있어서 역트리 모양이 되는 것을 보아야함

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 {
 
    // Complete the staircase function below.
    static void staircase(int n) {
 
        for (int i = 0; i < n; i++) {
            int startIndex = n - i - 2;
            String trees = "";
 
            for (int j = 0; j < n; j++) {
                if (j > startIndex) {
                    trees += "#";
                } else {
                    trees += " ";
                }
            }
 
            System.out.println(trees);
        }
 
    }
 
    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])?");
 
        staircase(n);
 
        scanner.close();
    }
}
 

[출처 : https://www.hackerrank.com ]