diff --git a/Chapter11/ds/line/stack/arr/Makefile b/Chapter11/ds/line/stack/arr/Makefile
new file mode 100644
index 0000000..a7681ed
--- /dev/null
+++ b/Chapter11/ds/line/stack/arr/Makefile
@@ -0,0 +1,31 @@
+# 方便起见一般都会先定义编译器链接器
+CC = gcc 
+LD = gcc
+
+# 正则表达式表示目录下所有.c文件，相当于：SRCS = main.c a.c b.c
+SRCS = $(wildcard *.c)
+
+# OBJS表示SRCS中把列表中的.c全部替换为.o，相当于：OBJS = main.o a.o b.o
+OBJS = $(patsubst %c, %o, $(SRCS))
+
+# 可执行文件的名字
+TARGET = main
+
+# .PHONE伪目标，具体含义百度一下一大堆介绍
+.PHONY:all clean
+
+# 要生成的目标文件
+all: $(TARGET)
+
+# 第一行依赖关系：冒号后面为依赖的文件，相当于Hello: main.o a.o b.o
+# 第二行规则：$@表示目标文件，$^表示所有依赖文件，$<表示第一个依赖文件
+$(TARGET): $(OBJS)
+	$(LD) -o $@ $^
+
+# 上一句目标文件依赖一大堆.o文件，这句表示所有.o都由相应名字的.c文件自动生成
+%.o:%.c
+	$(CC) -c $^
+
+# make clean删除所有.o和目标文件
+clean:
+	rm -f $(OBJS) $(TARGET)
diff --git a/Chapter11/ds/line/stack/arr/main.c b/Chapter11/ds/line/stack/arr/main.c
new file mode 100644
index 0000000..2b8f8dd
--- /dev/null
+++ b/Chapter11/ds/line/stack/arr/main.c
@@ -0,0 +1,41 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "sqstack.h"
+
+int main()
+{
+    datatype arr[] = {19, 23, 0, 45, 67};
+    sqstack *st;
+    int      i;
+
+    st = st_create();
+    if (NULL == st)
+        exit(1);
+
+    for (i = 0; i < sizeof(arr) / sizeof(*arr); i++)
+        st_push(st, &arr[i]);
+
+    st_travel(st);
+
+    datatype tmp;
+    while (0 == st_pop(st, &tmp))
+    {
+        printf("POP:%d\n", tmp);
+    }
+
+#if 0
+    datatype tmp = 1;
+    int      ret;
+    
+    ret = st_push(st, &tmp);
+    if (0 != ret)
+        printf("st_push failed.\n");
+    else
+        st_travel(st);
+
+    st_destroy(st);
+#endif
+
+    exit(0);
+}
\ No newline at end of file
diff --git a/Chapter11/ds/line/stack/arr/sqstack.c b/Chapter11/ds/line/stack/arr/sqstack.c
new file mode 100644
index 0000000..d10927d
--- /dev/null
+++ b/Chapter11/ds/line/stack/arr/sqstack.c
@@ -0,0 +1,72 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "sqstack.h"
+
+sqstack *st_create(void)
+{
+    sqstack *st;
+
+    st = malloc(sizeof(*st));
+    if (NULL == st)
+        return NULL;
+
+    st->top = -1;
+
+    return st;
+}
+
+int st_isempty(sqstack *st)
+{
+    return (-1 == st->top);
+}
+
+int st_push(sqstack *st, datatype *data)
+{
+    if (MAXSIZE - 1 == st->top)
+        return -1;
+
+    st->data[++st->top] = *data;
+
+    return 0;
+}
+
+/* 取出栈顶元素 */
+int st_pop(sqstack *st, datatype *data)
+{
+    if (st_isempty(st))
+        return -1;
+
+    *data = st->data[st->top--];
+
+    return 0;
+}
+
+
+/* 查看栈顶元素 */
+int st_top(sqstack *st, datatype *data)
+{
+    if (st_isempty(st))
+        return -1;
+
+    *data = st->data[st->top];
+
+    return 0;
+}
+
+void st_travel(sqstack *st)
+{
+    if (st_isempty(st))
+        return;
+
+    int i;
+
+    for (i = 0; i <= st->top; i++)
+        printf("%d ", st->data[i]);
+    printf("\n");
+}
+
+void st_destroy(sqstack *st)
+{
+    free(st);
+}
diff --git a/Chapter11/ds/line/stack/arr/sqstack.h b/Chapter11/ds/line/stack/arr/sqstack.h
new file mode 100644
index 0000000..f36cc58
--- /dev/null
+++ b/Chapter11/ds/line/stack/arr/sqstack.h
@@ -0,0 +1,30 @@
+#ifndef SQSTACK_H__
+#define SQSTACK_H__
+
+#define MAXSIZE 5
+
+typedef int datatype;
+
+typedef struct node_st
+{
+    datatype data[MAXSIZE];
+    int      top;
+} sqstack;
+
+sqstack *st_create(void);
+
+int st_isempty(sqstack *);
+
+int st_push(sqstack *, datatype *);
+
+/* 取出栈顶元素 */
+int st_pop(sqstack *, datatype *);
+
+/* 查看栈顶元素 */
+int st_top(sqstack *, datatype *);
+
+void st_travel(sqstack *);
+
+void st_destroy(sqstack *);
+
+#endif
\ No newline at end of file
diff --git a/Chapter11/ds/line/stack/list/Makefile b/Chapter11/ds/line/stack/list/Makefile
new file mode 100644
index 0000000..a7681ed
--- /dev/null
+++ b/Chapter11/ds/line/stack/list/Makefile
@@ -0,0 +1,31 @@
+# 方便起见一般都会先定义编译器链接器
+CC = gcc 
+LD = gcc
+
+# 正则表达式表示目录下所有.c文件，相当于：SRCS = main.c a.c b.c
+SRCS = $(wildcard *.c)
+
+# OBJS表示SRCS中把列表中的.c全部替换为.o，相当于：OBJS = main.o a.o b.o
+OBJS = $(patsubst %c, %o, $(SRCS))
+
+# 可执行文件的名字
+TARGET = main
+
+# .PHONE伪目标，具体含义百度一下一大堆介绍
+.PHONY:all clean
+
+# 要生成的目标文件
+all: $(TARGET)
+
+# 第一行依赖关系：冒号后面为依赖的文件，相当于Hello: main.o a.o b.o
+# 第二行规则：$@表示目标文件，$^表示所有依赖文件，$<表示第一个依赖文件
+$(TARGET): $(OBJS)
+	$(LD) -o $@ $^
+
+# 上一句目标文件依赖一大堆.o文件，这句表示所有.o都由相应名字的.c文件自动生成
+%.o:%.c
+	$(CC) -c $^
+
+# make clean删除所有.o和目标文件
+clean:
+	rm -f $(OBJS) $(TARGET)
diff --git a/Chapter11/ds/line/stack/list/llist.c b/Chapter11/ds/line/stack/list/llist.c
new file mode 100644
index 0000000..1190181
--- /dev/null
+++ b/Chapter11/ds/line/stack/list/llist.c
@@ -0,0 +1,130 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "llist.h"
+
+LLIST *llist_create(int initsize)
+{
+    LLIST *new;
+
+    new = malloc(sizeof(*new));   // !!! 不是sizeof(initsize),也不是new,是*new
+    if (NULL == new)
+        return NULL;
+
+    new->size      = initsize;
+    new->head.prev = &new->head;
+    new->head.next = &new->head;
+
+    return new;
+}
+
+int llist_insert(LLIST *ptr, const void *data, int mode)
+{
+    struct llist_node_st *newnode;
+
+    newnode = malloc(sizeof(*newnode) + ptr->size);   // -4
+    if (NULL == newnode)
+        return -1;
+
+    memcpy(newnode->data, data, ptr->size);
+
+    if (LLIST_FORWARD == mode)
+    {
+        newnode->prev = &ptr->head;
+        newnode->next = ptr->head.next;
+    }
+    else if (LLIST_BACKWARD == mode)
+    {
+        newnode->prev = ptr->head.prev;
+        newnode->next = &ptr->head;
+    }
+    else   // error
+    {
+        return -3;
+    }
+
+    // !!! 妙啊
+    newnode->next->prev = newnode;
+    newnode->prev->next = newnode;
+
+    return 0;
+}
+
+static struct llist_node_st *find_(LLIST *ptr, const void *key, llist_cmp *cmp)
+{
+    struct llist_node_st *cur;
+
+    for (cur = ptr->head.next; cur != &ptr->head; cur = cur->next)
+    {
+        if (0 == cmp(key, cur->data))
+            break;
+    }
+
+    return cur;   // 找不到的时候，返回的cur就是ptr，返回NULL
+}
+
+void *llist_find(LLIST *ptr, const void *key, llist_cmp *cmp)
+{
+    struct llist_node_st *node;
+    node = find_(ptr, key, cmp);
+    if (node == &ptr->head)
+        return NULL;
+
+    return node->data;
+}
+
+int llist_delete(LLIST *ptr, const void *key, llist_cmp *cmp)
+{
+    struct llist_node_st *node;
+
+    node = find_(ptr, key, cmp);
+    if (node == &ptr->head)
+        return -1;
+
+    // !!!
+    node->prev->next = node->next;
+    node->next->prev = node->prev;
+    free(node);
+    return 0;
+}
+
+int llist_fetch(LLIST *ptr, const void *key, llist_cmp *cmp, void *data)
+{
+    struct llist_node_st *node;
+
+    node = find_(ptr, key, cmp);
+    if (node == &ptr->head)
+        return -1;
+
+    node->next->prev = node->prev;
+    node->prev->next = node->next;
+
+    if (data != NULL)
+        memcpy(data, node->data, ptr->size);
+
+    free(node);
+
+    return 0;
+}
+
+void llist_travel(LLIST *ptr, llist_op *op)
+{
+    struct llist_node_st *cur;
+
+    for (cur = ptr->head.next; cur != &ptr->head; cur = cur->next)
+        op(cur->data);
+}
+
+void llist_destroy(LLIST *ptr)
+{
+    struct llist_node_st *cur, *next;
+
+    for (cur = ptr->head.next; cur != &ptr->head; cur = next)
+    {
+        next = cur->next;
+        free(cur);
+    }
+
+    free(ptr);
+}
diff --git a/Chapter11/ds/line/stack/list/llist.h b/Chapter11/ds/line/stack/list/llist.h
new file mode 100644
index 0000000..48457e4
--- /dev/null
+++ b/Chapter11/ds/line/stack/list/llist.h
@@ -0,0 +1,39 @@
+#ifndef LLIST_H__
+#define LLIST_H__
+
+#define LLIST_FORWARD  1
+#define LLIST_BACKWARD 2
+
+// !!! 变长结构体
+struct llist_node_st
+{
+    struct llist_node_st *prev;
+    struct llist_node_st *next;
+    // data要放在最后
+    char data[1];   // 占位符，数据的起始。C99才只是[0]
+};
+
+typedef struct
+{
+    int                  size;
+    struct llist_node_st head;
+} LLIST;
+
+typedef void llist_op(const void *);
+typedef int  llist_cmp(const void *, const void *);
+
+LLIST *llist_create(int initsize);
+
+int llist_insert(LLIST *ptr, const void *data, int mode);
+
+void *llist_find(LLIST *ptr, const void *key, llist_cmp *);
+
+int llist_delete(LLIST *, const void *key, llist_cmp *);
+
+int llist_fetch(LLIST *, const void *key, llist_cmp *, void *data);
+
+void llist_travel(LLIST *ptr, llist_op *op);
+
+void llist_destroy(LLIST *ptr);
+
+#endif
diff --git a/Chapter11/ds/line/stack/list/main.c b/Chapter11/ds/line/stack/list/main.c
new file mode 100644
index 0000000..72312b6
--- /dev/null
+++ b/Chapter11/ds/line/stack/list/main.c
@@ -0,0 +1,55 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "stack.h"
+
+#define NAMESIZE 32
+
+struct score_st
+{
+    int  id;
+    char name[NAMESIZE];
+    int  math;
+    int  chinese;
+};
+
+static int print_s(void *record)
+{
+    struct score_st *r = record;
+
+    printf("%d %s %d %d\n", r->id, r->name, r->math, r->chinese);
+}
+
+int main()
+{
+    STACK          *st;
+    struct score_st tmp;
+    int             i, ret;
+
+    st = stack_create(sizeof(struct score_st));
+    if (NULL == st)
+        exit(1);
+
+    for (i = 0; i < 7; i++)
+    {
+        tmp.id = i;
+        snprintf(tmp.name, NAMESIZE, "stu%d", i);
+        tmp.math    = rand() % 100;
+        tmp.chinese = rand() % 100;
+
+        if (stack_push(st, &tmp))
+            exit(1);
+    }
+
+    while (1)
+    {
+        ret = stack_pop(st, &tmp);
+        if (-1 == ret)
+            break;
+        print_s(&tmp);
+    }
+
+    stack_destroy(st);
+
+    exit(0);
+}
\ No newline at end of file
diff --git a/Chapter11/ds/line/stack/list/stack.c b/Chapter11/ds/line/stack/list/stack.c
new file mode 100644
index 0000000..10950c3
--- /dev/null
+++ b/Chapter11/ds/line/stack/list/stack.c
@@ -0,0 +1,29 @@
+#include <stdio.h>
+
+#include "stack.h"
+
+LLIST *stack_create(int initsize)
+{
+    return llist_create(initsize);
+}
+
+int stack_push(STACK *ptr, const void *data)
+{
+    return llist_insert(ptr, data, LLIST_FORWARD);
+}
+
+static int always_match(const void *p1, const void *p2)
+{
+    return 0;
+}
+
+int stack_pop(STACK *ptr, void *data)
+{
+    // !!! 假接口
+    return llist_fetch(ptr, (void *)0, always_match, data);
+}
+
+void stack_destroy(STACK *ptr)
+{
+    llist_destroy(ptr);
+}
\ No newline at end of file
diff --git a/Chapter11/ds/line/stack/list/stack.h b/Chapter11/ds/line/stack/list/stack.h
new file mode 100644
index 0000000..630f5e4
--- /dev/null
+++ b/Chapter11/ds/line/stack/list/stack.h
@@ -0,0 +1,16 @@
+#ifndef STACK_H__
+#define STACK_H__
+
+#include "llist.h"
+
+typedef LLIST STACK;
+
+STACK *stack_create(int);
+
+int stack_push(STACK *, const void *data);
+
+int stack_pop(STACK *, void *data);
+
+void stack_destroy(STACK *);
+
+#endif
\ No newline at end of file