《数据结构》严蔚敏 用栈实现括号匹配检验

思路：将符合要求的符号"[“和”(“添加到栈中，然后将每一次输入的”]“和”)"与栈顶元素利用ascii码值来进行比较，如果匹配则将栈中压入的元素弹出，否则继续匹配下一个。当输入结束符“#”时，若栈为空，则匹配成功，否则，匹配失败

核心代码：
int match(char p,char q)
void parenthesis_matching(SqStack * S)

程序截图：

//Order Stack
//parenthesis mathing


#include<stdio.h>
#include<stdlib.h>

#define STACK_INIT_SIZE 100
#define STACKINCREMENT  10
#define EXPRESSION_SIZE 100

#define TRUE 1
#define FALSE 0
#define OK 1
#define ERROR 0


typedef char SElemType;
typedef int Status;

typedef struct
{
	SElemType *base;
	SElemType *top;

	int stackesize;

}SqStack;

Status
InitStack(SqStack *S)
{
	(*S).base =(SElemType *)malloc(STACK_INIT_SIZE * sizeof(SqStack));
	//why first I used the (*S).top ???
	//the verfy I always forget... So my code always weak...
	if(!S->base)
		exit(ERROR);

	(*S).top = (*S).base; // If you don't understand it ,I think you should learn about the structure in C firstly.
	(*S).stackesize = STACK_INIT_SIZE;

	return OK;
}


Status StackEmpty(SqStack *S)
{
	if(S->top == S->base)
		return TRUE;
	else
		return FALSE;

	// or use ? : make things seems concise

}

// When Push,first add then change the point

Status
Push(SqStack *S,SElemType e)
{
	//lack of verfy
	if(S->top - S->base >= S->stackesize)
	{
		S->base = (SElemType*)realloc(S->base,
			(S->stackesize + STACK_INIT_SIZE)*sizeof(SElemType));
		if(!S->base)
			exit(ERROR);
		S->top = S->base + S->stackesize;
		S->stackesize += STACKINCREMENT;
	}
	

	////////// the first ////
	*(*S).top = e;
	S->top ++;
	
	return OK;	

}

//when pop,first change point then pop element

Status
Pop(SqStack *S)
{
	if(StackEmpty(S) == 0)
	{
		S->top --;
		return OK;
	}
	else
		return ERROR;

}

char
top(SqStack *S,char * e)
{
	if(S->top == S->base)
		return ERROR;
	else
		*e = *(S->top -1);

	return OK;

}

//use the ascill to compare

int
match(char p,char q)
{
	if(abs(p-q) == 1)
    return 1;
    else if(abs(p-q) == 2)
    return 1;
    else
    return 0;
}

void
parenthesis_matching(SqStack * S)
{
	char top_value;	
	char expression[EXPRESSION_SIZE];
	printf("please enter the expression: (end with #) ");
	for(int i = 0;i<EXPRESSION_SIZE;i++)
	{
		scanf("%c",&expression[i]);
		
		if(expression[i] == '[' || expression[i] == '(')
		{
			Push(S,expression[i]);
			
			continue;
		}
		if(expression[i] == ']' || expression[i] == ')')
		{
			top(S,&top_value);
			if(match(expression[i],top_value))
			{
				Pop(S);
				
			}
			continue;
		}

		if(expression[i] == '#')
			break;
		
	}

	if(StackEmpty(S) == 1)
		printf("the parenthesis_matching right!\n");
	else
		printf("the parenthesis_matching wrong!\n");

	

}

int main(int argc, char const *argv[])
{
	SqStack S;
	int expression_value;
	InitStack(&S);
	
	parenthesis_matching(&S);


	return 0;
}