feat: generate parentheses (#361)

strings/generateparentheses/generateparentheses.go

@@ -0,0 +1,34 @@
+// generateparenthesesgo
+// description: Generate Parentheses
+// details:
+// Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.
+// author(s) [red_byte](https://github.com/i-redbyte)
+// see generateparentheses_test.go
+
+package generateparentheses
+
+import "strings"
+
+func GenerateParenthesis(n int) []string {
+	result := make([]string, 0)
+	maxLen := 2 * n
+	var recursiveComputation func(s []string, left int, right int)
+	recursiveComputation = func(s []string, left int, right int) {
+		if len(s) == maxLen {
+			result = append(result, strings.Join(s, ""))
+			return
+		}
+		if left < n {
+			s = append(s, "(")
+			recursiveComputation(s, left+1, right)
+			s = s[:len(s)-1]
+		}
+		if right < left {
+			s = append(s, ")")
+			recursiveComputation(s, left, right+1)
+			_ = s[:len(s)-1]
+		}
+	}
+	recursiveComputation(make([]string, 0), 0, 0)
+	return result
+}

strings/generateparentheses/generateparentheses_test.go

@@ -0,0 +1,21 @@
+// generateparentheses_test.go
+// description: Generate Parentheses
+// author(s) [red_byte](https://github.com/i-redbyte)
+// see generateparentheses.go
+
+package generateparentheses
+
+import "testing"
+
+func TestGenerateParenthesis(t *testing.T) {
+	t.Run("GenerateParenthesis", func(t *testing.T) {
+		result := GenerateParenthesis(3)
+		t.Log(result)
+		exp := []string{"((()))", "(()())", "(())()", "()(())", "()()()"}
+		for i, v := range result {
+			if v != exp[i] {
+				t.Errorf("Wrong result! Expected:%s, returned:%s ", result[i], exp[i])
+			}
+		}
+	})
+}