[Hacker Rank]: Staircase solved ✓

Author: Gonzalo Diaz

docs/hackerrank/warmup/staircase.md

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+# [Staircase](https://www.hackerrank.com/challenges/staircase)
+
+Difficulty: #easy
+Category: #warmup
+
+Staircase detail
+This is a staircase of size $ n = 4 $:
+
+```text
+   #
+  ##
+ ###
+####
+```
+
+Its base and height are both equal to n. It is drawn using # symbols
+and spaces. The last line is not preceded by any spaces.
+
+Write a program that prints a staircase of size n.
+
+## Function Description
+
+Complete the staircase function in the editor below.
+
+staircase has the following parameter(s):
+
+* int n: an integer
+
+## Print
+
+Print a staircase as described above.
+
+## Input Format
+
+A single integer, , denoting the size of the staircase.
+
+Constraints
+
+$ 0 < n \leq 100 $
+
+## Output Format
+
+Print a staircase of size n using # symbols and spaces.
+
+Note: The last line must have  spaces in it.
+
+## Sample Input
+
+```text
+6
+```
+
+## Sample Output
+
+```text
+     #
+    ##
+   ###
+  ####
+ #####
+######
+```
+
+## Explanation
+
+The staircase is right-aligned, composed of # symbols and spaces,
+and has a height and width of $ n = 6 $.

src/pkg/hackerrank/warmup/staircase.go

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+/**
+ * @link Problem definition [[docs/hackerrank/warmup/staircase.md]]
+ */
+
+package hackerrank
+
+import (
+	"strings"
+
+	utils "gon.cl/algorithm-exercises/src/utils"
+)
+
+func Staircase(n int) string {
+
+	result := []string{}
+
+	for i := 1; i <= n; i++ {
+		line := ""
+
+		for j := 1; j <= n; j++ {
+			if j <= n-i {
+				line = line + " "
+			} else {
+				line = line + "#"
+			}
+		}
+
+		result = append(result, line)
+	}
+
+	utils.Info("Staircase answer => %v", result)
+
+	return strings.Join(result, "\n")
+}

src/pkg/hackerrank/warmup/staircase_test.go

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+package hackerrank
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestStaircase(t *testing.T) {
+
+	input := 6
+	expectedSolution := strings.Join([]string{
+		"     #",
+		"    ##",
+		"   ###",
+		"  ####",
+		" #####",
+		"######",
+	}, "\n")
+
+	testname := fmt.Sprintf("Staircase(%d) => %v \n", input, expectedSolution)
+	t.Run(testname, func(t *testing.T) {
+
+		ans := Staircase(input)
+		assert.Equal(t, expectedSolution, ans)
+	})
+}