feat(go/backtracking): add go code (#488)

* feat(go/backtracking): add go code

* feat(backtracking): add n_queens in go

* feat(backtracking): add /preorder_traversal_i_compact in go

* feat(backtracking): add /preorder_traversal_ii_compact in go

* feat(backtracking): add /preorder_traversal_ii_template in go

* feat(backtracking): add preorder_traversal_iii_compact in go

* feat(backtracking): add preorder_traversal_test in go

* feat(backtracking): add permutations_i in go

* feat(backtracking): add permutations_ii in go

* feat(backtracking): add permutation_test in go

* feat(backtracking): fix bug in go

* Update permutations_i.go

---------

Co-authored-by: Yudong Jin <krahets@163.com>

codes/go/chapter_backtracking/permutation_test.go

@@ -0,0 +1,33 @@
+// File: preorder_traversal_i_compact_test.go
+// Created Time: 2023-05-09
+// Author: Reanon (793584285@qq.com)
+
+package chapter_backtracking
+
+import (
+	"fmt"
+	"testing"
+
+	. "github.com/krahets/hello-algo/pkg"
+)
+
+func TestPermutationI(t *testing.T) {
+	/* 全排列 I */
+	nums := []int{1, 2, 3}
+	fmt.Printf("输入数组 nums = ")
+	PrintSlice(nums)
+
+	res := permutationsI(nums)
+	fmt.Printf("所有排列 res = ")
+	fmt.Println(res)
+}
+
+func TestPermutationII(t *testing.T) {
+	nums := []int{1, 2, 2}
+	fmt.Printf("输入数组 nums = ")
+	PrintSlice(nums)
+
+	res := permutationsII(nums)
+	fmt.Printf("所有排列 res = ")
+	fmt.Println(res)
+}