顺序栈：

一、数据结构定义

1. 数据元素 DATATYPE

typedef struct person {char name[32];char sex;int age;int score;
} DATATYPE;

1. 顺序栈结构 SeqStack

typedef struct list {DATATYPE *head;  // 栈空间首地址int tlen;        // 栈总容量（total length）int top;         // 栈顶指针（相当于当前元素计数）
} SeqStack;

二、核心操作接口

1. 创建栈

SeqStack *CreateSeqStack(int size)
{SeqStack *ss = malloc(sizeof(SeqStack));if (NULL == ss){perror("CreateSeqStack malloc error\n");return NULL;}ss->head = malloc(sizeof(DATATYPE) * size);if (NULL == ss){perror("CreateSeqStack malloc2 error\n");return NULL;}ss->tlen = size;ss->top = 0;return ss;
}

• 实现要点：
  • 动态分配结构体内存
  • 分配连续存储空间：head = malloc(size * sizeof(DATATYPE))
  • 初始化tlen = size, top = 0

1. 销毁栈

int DestroySeqStack(SeqStack *ss)
{if (NULL == ss){fprintf(stderr, "DestroySeqStack pamter error\n");return 1;}free(ss->head);free(ss);return 0;
}

• 内存释放顺序：
  1. 释放数据空间 free(ss->head)
  2. 释放控制结构 free(ss)

1. 入栈操作

int PushSeqStack(SeqStack *ss, DATATYPE *data) // add
{if (NULL == ss || NULL == data || IsFullSeqStack(ss)){fprintf(stderr, "PushSeqStack pamter error\n");return 1;}memcpy(&ss->head[ss->top], data, sizeof(DATATYPE));ss->top++;return 0;
}

• 实现流程：

if 栈未满：复制数据到ss->head[top]位置top++返回成功
else：返回失败

1. 出栈操作

int PopSeqStack(SeqStack *ss)
{if (NULL == ss){fprintf(stderr, "PopSeqStack pamter error\n");return 1;}ss->top--;return 0;
}

• 实现逻辑：

if 栈非空：top--返回成功
else：返回失败

1. 判空操作

int IsEmpySeqStack(SeqStack *ss)
{return 0 == ss->top;
}

• 判断条件：top == 0

1. 判满操作

int IsFullSeqStack(SeqStack *ss)
{return ss->tlen == ss->top;
}

• 判断条件：top == tlen

1. 获取栈顶元素

DATATYPE *GetTopSeqStack(SeqStack *ss)
{if (NULL == ss || IsEmpySeqStack(ss)){fprintf(stderr, "GetTopSeqStack pamter error\n");return NULL;}return &ss->head[ss->top - 1];
}

• 注意点：
  • 返回ss->head[top-1]的地址
  • 需先判断栈是否为空

1. 获取栈大小

int GetSizeSeqStack(SeqStack *ss)
{if (NULL == ss ){fprintf(stderr, "GetSizeSeqStack pamter error\n");return 1;}return ss->top;
}

• 直接返回top值

三、存储结构示意图

栈底 → head[0]head[1]...
栈顶 → head[top-1]  ← 当前有效元素head[top]    ← 下一个可用位置（当top<tlen时）...head[tlen-1]

四、时间复杂度分析

操作	时间复杂度	说明
创建栈	O(1)	内存分配操作
销毁栈	O(1)	内存释放操作
入栈/出栈	O(1)	直接操作栈顶指针
获取栈顶元素	O(1)	随机访问特性
获取栈大小	O(1)	直接读取top值

五、优势与局限

1. 优势：

   • 随机访问特性，支持快速定位
   • 内存连续，缓存命中率高
   • 操作时间复杂度均为O(1)

2. 局限：

   • 固定容量，需要预先分配空间
   • 扩容成本高（需要重新分配内存）
   • 可能产生空间浪费（分配未使用的空间）

六、典型应用场景

1. 函数调用栈的实现
2. 表达式求值（中缀转后缀表达式）
3. 括号匹配检测
4. 浏览器的后退操作栈
5. 撤销/重做功能实现

七、实现注意事项

1. 内存管理：

   • 创建时需分配两次内存（控制结构+数据空间）
   • 销毁时需按相反顺序释放

2. 临界条件处理：

   • 入栈前必须检查栈是否已满
   • 出栈前必须检查栈是否为空
   • 获取栈顶元素前必须检查非空

八、实际应用

1.符号匹配

main 函数

#include "./SeqStack.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
int do_check(char *buf, SeqStack *ss, int num)
{int col = 1;DATATYPE data;while (*buf){DATATYPE *tmp = NULL;bzero(&data, sizeof(data));int c = *buf;switch (c){case '(':case '[':case '{':handle_left_bracket(c, num, col, &data, ss);break;case ')':case ']':case '}':if (handle_right_bracket(c, num, col, ss)){return 1;}break;}buf++;col++;}return 0;
}// 封装左括号的处理逻辑
void handle_left_bracket(int c, int num, int col, DATATYPE *data, SeqStack *ss)
{data->sym = c;data->linenum = num;data->colnum = col;PushSeqStack(ss, data);
}// 封装右括号的处理逻辑
int handle_right_bracket(int c, int num, int col, SeqStack *ss)
{DATATYPE *tmp = GetTopSeqStack(ss);if (tmp == NULL){printf("read sym:%c ,line:%d col:%d\n", c, num, col);return 1;}if ((c == ')' && tmp->sym == '(') ||(c == ']' && tmp->sym == '[') ||(c == '}' && tmp->sym == '{')){PopSeqStack(ss);return 0;}else{printf("read sym:%c ,line:%d col:%d  or top sym:%c ,line:%d col:%d\n", c, num, col, tmp->sym, tmp->linenum, tmp->colnum);return 1;}
}
int main(int argc, char const *argv[])
{SeqStack *ss = CreateSeqStack(5);FILE *fp = fopen("./open.c", "r+");if (NULL == fp){perror("fopen");return 1;}int num = 1;int ret = 0;while (1){char buf[256] = {0};if (NULL == fgets(buf, sizeof(buf), fp)){break;}ret = do_check(buf, ss, num);if(1== ret){DestroySeqStack(ss);exit(1);}num++;/* code */}if(IsEmpySeqStack(ss)){printf("file ok\n");}else{DATATYPE *tmp = GetTopSeqStack(ss);printf("top sym:%c ,line:%d col:%d\n", tmp->sym, tmp->linenum, tmp->colnum);}return 0;
}

2.四则运算（栈）

int applyOperator(int a, int b, char op)
{switch (op){case '+':return a + b;case '-':return a - b;case '*':return a * b;case '/':return a / b;default:fprintf(stderr, "applyOperator error\n");return 0;}
}
int precedence(char op)
{if (op == '+' || op == '-'){return 1;}if (op == '*' || op == '/'){return 2;}return 0;
}
int evaluateExpression(char *expression)
{SeqStack *operand = CreateSeqStack(100);SeqStack *opertor = CreateSeqStack(100);int i = 0;while (expression[i] != '\0'){char c = expression[i];if (isdigit(c)){int num = 0;while (isdigit(expression[i])){num = num * 10 + (expression[i] - '0');i++;}DATATYPE data;data.op = '0';data.num = num;PushSeqStack(operand, &data);}else if (c == '+' || c == '-' || c == '*' || c == '/'){while (!IsEmpySeqStack(opertor) && precedence(c) <= precedence(GetTopSeqStack(opertor)->op)){DATATYPE opData = *GetTopSeqStack(opertor);PopSeqStack(opertor);DATATYPE bData = *GetTopSeqStack(operand);PopSeqStack(operand);DATATYPE aData = *GetTopSeqStack(operand);PopSeqStack(operand);int ret = applyOperator(aData.num, bData.num, opData.op);DATATYPE retData;retData.op = '0';retData.num = ret;PushSeqStack(operand, &retData);}DATATYPE data;data.op = c;PushSeqStack(opertor, &data);i++;}else{i++;}}// 处理运算符栈中剩余的运算符while (!IsEmpySeqStack(opertor)){DATATYPE opData = *GetTopSeqStack(opertor);PopSeqStack(opertor);DATATYPE bData = *GetTopSeqStack(operand);PopSeqStack(operand);DATATYPE aData = *GetTopSeqStack(operand);PopSeqStack(operand);int ret = applyOperator(aData.num, bData.num, opData.op);DATATYPE retData;retData.op = '0';retData.num = ret;PushSeqStack(operand, &retData);}int result = GetTopSeqStack(operand)->num;DestroySeqStack(operand);DestroySeqStack(opertor);return result;
}

链式栈（Linked Stack）

---

一、链式栈核心结构

1. 节点定义

// 数据元素类型
typedef struct person {char name[32];char sex;int age;int score;
} DATATYPE;// 栈节点结构
typedef struct stacknode {DATATYPE data;           // 数据域struct stacknode *next;  // 指针域
} LinkStackNode;// 栈管理结构
typedef struct list {LinkStackNode *top;      // 栈顶指针int clen;                // 当前元素个数
} LinkStack;

---

二、核心操作实现

1. 创建空栈

LinkStack*CreateLinkStack()
{LinkStack* ls = malloc(sizeof(LinkStack));if(NULL == ls){perror("CreateLinkStack malloc error\n");return NULL;}ls->top = NULL;ls->clen = 0;return ls;}

2. 销毁栈

int DestroyLinkStack(LinkStack*ls)
{if(NULL == ls ){fprintf(stderr,"DestroyLinkStack paramter error\n");return 1;}while(!IsEmptyLinkStack(ls)){PopLinkStack(ls);}free(ls);return 0;
}

---

三、栈操作实现

1. 入栈操作

int PushLinkStack(LinkStack*ls,DATATYPE*data)
{if(NULL == ls || NULL == data){fprintf(stderr,"PushLinkStack paramter error\n");return 1;}LinkStackNode* newnode = malloc(sizeof(LinkStackNode));if(NULL == newnode){perror("PushLinkStack malloc error\n");return 1;}memcpy(&newnode->data,data,sizeof(DATATYPE));newnode->next = NULL;if(IsEmptyLinkStack(ls)){ls->top = newnode;}else {newnode->next = ls->top;ls->top = newnode;}ls->clen++;return 0;}

2. 出栈操作

int PopLinkStack(LinkStack*ls)
{if(NULL == ls  ){fprintf(stderr,"PopLinkStack paramter error\n");return 1;}if(IsEmptyLinkStack(ls)){fprintf(stderr,"PopLinkStack empty\n");return 1;}LinkStackNode* tmp = ls->top;ls->top = ls->top->next;free(tmp);ls->clen--;return 0;}

---

四、辅助操作实现

1. 判空检测

int IsEmptyLinkStack(LinkStack* ls) {return ls->clen == 0;// 或 return ls->top == NULL;
}

2. 获取栈顶元素

DATATYPE*GetTopLinkStack(LinkStack*ls)
{if(NULL == ls  ){fprintf(stderr,"GetTopLinkStack paramter error\n");return NULL;}if(IsEmptyLinkStack(ls)){fprintf(stderr,"GetTopLinkStack empty\n");return NULL;}return &ls->top->data;
}

3. 获取栈大小

int GetSizeLinkStack(LinkStack* ls) {return ls->clen;
}

---

五、链式栈 VS 顺序栈

对比维度	链式栈	顺序栈
存储结构	离散内存节点	连续内存空间
容量限制	动态扩展	固定大小
内存开销	每个节点含指针（+8/16字节）	无额外开销
入栈操作	动态分配内存	可能需扩容
缓存友好性	较差	优秀
实现复杂度	需处理指针操作	数组索引操作简单

---

六、典型应用场景

1. 函数调用栈

void funcA() {// 保存当前上下文入栈funcB();// 弹出上下文
}void funcB() {// 新的栈帧入栈
}

2. 表达式求值

// 中缀转后缀表达式算法
while(输入队列不为空) {读取token;if(是数字) 加入输出队列;else if(是运算符) {while(栈顶运算符优先级 >= 当前运算符)弹出栈顶到输出队列;当前运算符入栈;}
}

3. 括号匹配检测

bool isValid(char* s) {LinkStack *ls = CreateLinkStack();while(*s) {if(*s == '(' || *s == '[' || *s == '{') {PushLinkStack(ls, *s);} else {if(IsEmptyLinkStack(ls)) return false;char top = GetTopLinkStack(ls);if((*s == ')' && top != '(') ||(*s == ']' && top != '[') ||(*s == '}' && top != '{')) return false;PopLinkStack(ls);}s++;}return IsEmptyLinkStack(ls);
}