Add Soulution.go for 0022.Generate Parentheses

Author: Yeqi Tao

solution/0022.Generate Parentheses/Solution.go

@@ -0,0 +1,19 @@
+func generateParenthesis(n int) []string {
+	result := make([]string, 0)
+	backParenthesis(&result, "", 0, 0, n)
+	return result
+}
+
+func backParenthesis(result *[]string, cur string, open, close, max int) {
+	if len(cur) == 2 * max {
+		*result = append(*result, cur)
+		return
+	}
+
+	if open < max {
+		backParenthesis(result, cur+"(", open+1, close, max)
+	}
+	if close < open {
+		backParenthesis(result, cur+")", open, close+1, max)
+	}
+}