diff --git a/datastruct/list.h b/datastruct/list.h
index f4040d1..ab46d29 100644
--- a/datastruct/list.h
+++ b/datastruct/list.h
@@ -56,7 +56,7 @@ struct _list
 	bool (*remove)(struct _list* self, int index);						// 根据索引，移除对象
 
 	int (*index)(struct _list* self, void* obj);						// 在列表中，查找数据是否存在，若存在则返回其索引。否则返回-1
-	bool (*at)(struct _list* self, int index, void* obj);			// 根据索引，获取对象
+	bool (*at)(struct _list* self, int index, void* obj);				// 根据索引，获取对象
 	bool (*set)(struct _list* self, int index, void* obj);				// 根据索引，修改对象
 
 	// base
diff --git a/datastruct/list_test.c b/datastruct/list_test.c
index 3a3aba7..db62b22 100644
--- a/datastruct/list_test.c
+++ b/datastruct/list_test.c
@@ -1,73 +1,6 @@
-
+#define _CRT_SECURE_NO_WARNINGS 1
 #include "list.h"
 
-#if 0
-void list_test(void)
-{
-	int i = 0;
-
-	list_data_t data = 0;
-	struct _list list;
-	list_init(&list);
-
-	printf("----- append -----\n");
-	for (i = 0; i < 18; i++)
-	{
-		list_append(&list, i);
-		list_print(&list);
-	}
-
-	printf("----- delete -----\n");
-	list_delete(&list, 17);
-	list_print(&list);
-
-	list_delete(&list, 0);
-	list_print(&list);
-
-	list_delete(&list, 9);
-	list_print(&list);
-
-	printf("----- clear -----\n");
-	list_clear(&list);
-	printf("----- insert -----\n");
-	for (i = 0; i < 18; i++)
-	{
-		list_insert(&list, 0, i);
-		list_print(&list);
-	}
-
-	printf("----- get -----\n");
-	data = list_get(&list, 0);
-	printf("list[0] = %2d\n", data);
-
-	data = list_get(&list, 17);
-	printf("list[17] = %2d\n", data);
-
-	data = list_get(&list, 5);
-	printf("list[5] = %2d\n", data);
-
-	printf("----- like python -----\n");
-	data = list_get(&list, -1);
-	printf("list[-1] = %2d\n", data);
-
-	data = list_get(&list, -5);
-	printf("list[-5] = %2d\n", data);
-
-	data = list_get(&list, -18);
-	printf("list[-18] = %2d\n", data);
-
-	printf("----- set -----\n");
-	for (i = 0; i < 18; i++)
-	{
-		list_set(&list, i, i);
-		list_print(&list);
-	}
-
-	list_print(&list);
-	list_destory(&list);
-}
-#endif
-
 static void print_num(void* obj)
 {
 	printf("(%2d )", *(int*)obj);
@@ -125,32 +58,32 @@ static void list_test_num(void)
 	printf("----- at -----\n");
 	index = 0;
 	list.at(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	index = 4;
 	list.at(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	index = 9;
 	list.at(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 
 	printf("----- set -----\n");
 	index = 0;
 	temp = 11;
 	list.set(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	index = 4;
 	temp = 22;
 	list.set(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	index = 9;
 	temp = 33;
 	list.set(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	printf("----- print -----\n");
 	list.print(&list);
@@ -160,31 +93,31 @@ static void list_test_num(void)
 	printf("----- at like python -----\n");
 	index = -1;
 	list.at(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	index = -6;
 	list.at(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	index = -10;
 	list.at(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	printf("----- set like python -----\n");
 	index = -1;
 	temp = 99;
 	list.set(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	index = -6;
 	temp = 98;
 	list.set(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	index = -10;
 	temp = 97;
 	list.set(&list, index, &temp);
-	printf("list[%2d] = %2d\n", index, temp);
+	printf("list[%4d] = %2d\n", index, temp);
 
 	printf("----- print -----\n");
 	list.print(&list);
@@ -193,16 +126,7 @@ static void list_test_num(void)
 	printf("----- pop -----\n");
 	for (i = 0; i < len + 1; i++)
 	{
-		if (true == list.pop(&list, 0, &temp))
-		{
-			printf("top = ");
-			list.print_obj(&temp);
-			printf("\tsize after push = %2d\n", list.size(&list));
-		}
-		else
-		{
-			printf("pop failed! because stack is empty\n");
-		}
+		list.pop(&list, 0, &temp);
 
 		if (list.empty(&list))
 		{
@@ -215,7 +139,174 @@ static void list_test_num(void)
 }
 
 
+struct _student
+{
+	char name[16];
+	int id;
+};
+
+static void print_struct(void* obj)
+{
+	struct _student* student = (struct _student*)obj;
+	printf("(%4d:%-8s) ", student->id, student->name);
+}
+
+static void list_test_struct(void)
+{
+	int i = 0;
+	struct _student data[] = {
+		"zhao", 1001, "qian", 1002, "sun",   1003, "li",   1004,
+		"zhou", 1005, "wu",   1006, "zheng", 1007, "wang", 1008, 
+		"feng", 1009, "cheng",1010, 
+	};
+	struct _student  temp = {0};
+	int index = 0;
+	int len = sizeof(data) / sizeof(data[0]);
+
+	struct _list list;
+	list_init(&list, sizeof(struct _student));
+	list.print_obj = print_struct;
+
+	printf("\n\n----- list_test_num -----\n");
+	printf("----- push -----\n");
+	for (i = 0; i < len; i++)
+	{
+		list.append(&list, &data[i]);
+	}
+	printf("----- print -----\n");
+	list.print(&list);
+	printf("\n");
+
+	printf("----- remove -----\n");
+	list.remove(&list, 9);
+	list.print(&list);
+	printf("\n");
+
+	list.remove(&list, 0);
+	list.print(&list);
+	printf("\n");
+
+	list.remove(&list, 4);
+	list.print(&list);
+	printf("\n");
+
+	printf("----- clear -----\n");
+	list.clear(&list);
+	list.print(&list);
+	printf("\n");
+
+	printf("----- push -----\n");
+	for (i = 0; i < len; i++)
+	{
+		list.append(&list, &data[i]);
+	}
+	printf("----- print -----\n");
+	list.print(&list);
+	printf("\n");
+
+	printf("----- at -----\n");
+	index = 0;
+	list.at(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	index = 4;
+	list.at(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	index = 9;
+	list.at(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+
+	printf("----- set -----\n");
+	index = 0;
+	temp.id = 11;
+	sprintf(temp.name, "robot_%02d", temp.id);
+	list.set(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	index = 4;
+	temp.id = 22;
+	sprintf(temp.name, "robot_%02d", temp.id);
+	list.set(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	index = 9;
+	temp.id = 33;
+	sprintf(temp.name, "robot_%02d", temp.id);
+	list.set(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	printf("----- print -----\n");
+	list.print(&list);
+	printf("\n");
+
+
+	printf("----- at like python -----\n");
+	index = -1;
+	list.at(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	index = -6;
+	list.at(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	index = -10;
+	list.at(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	printf("----- set like python -----\n");
+	index = -1;
+	temp.id = 99;
+	sprintf(temp.name, "robot_%02d", temp.id);
+	list.set(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	index = -6;
+	temp.id = 98;
+	sprintf(temp.name, "robot_%02d", temp.id);
+	list.set(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	index = -10;
+	temp.id = 97;
+	sprintf(temp.name, "robot_%02d", temp.id);
+	list.set(&list, index, &temp);
+	printf("list[%4d] = ", index);
+	list.print_obj(&temp); printf("\n");
+
+	printf("----- print -----\n");
+	list.print(&list);
+	printf("\n");
+
+	printf("----- pop -----\n");
+	for (i = 0; i < len + 1; i++)
+	{
+		list.pop(&list, 0, &temp);
+
+		if (list.empty(&list))
+		{
+			printf("----- empty -----\n");
+			break;
+		}
+	}
+
+	list.destory(&list);
+}
+
 void list_test(void)
 {
 	list_test_num();
+	list_test_struct();
 }