feat(go): add iterration/recursion & fix bugs (#698)

codes/go/chapter_computational_complexity/iteration_test.go

@@ -0,0 +1,26 @@
+// File: iteration_test.go
+// Created Time: 2023-08-28
+// Author: Reanon (793584285@qq.com)
+
+package chapter_computational_complexity
+
+import (
+	"fmt"
+	"testing"
+)
+
+/* Driver Code */
+func TestIteration(t *testing.T) {
+	n := 5
+	res := forLoop(n)
+	fmt.Println("\nfor 循环的求和结果 res = ", res)
+
+	res = whileLoop(n)
+	fmt.Println("\nwhile 循环的求和结果 res = ", res)
+
+	res = whileLoopII(n)
+	fmt.Println("\nwhile 循环（两次更新）求和结果 res = ", res)
+
+	resStr := nestedForLoop(n)
+	fmt.Println("\n双层 for 循环的遍历结果 ", resStr)
+}