C语言中缀表达式转后缀表达式

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <ctype.h>
#define  STACK_INIT_SIZE 100
#define STACKINCREMENT 10
typedef char ElemType;

typedef struct
{
	ElemType *base;
	ElemType *top;
	int stackSize;
}SqStack;

//创建一个栈
void initStack(SqStack *s) {
	s->base = (ElemType *)malloc(sizeof(ElemType));
	if (!s->base)
	{
		exit(0);
	}
	s->top = s->base;   //最开始 栈底就是栈顶
	s->stackSize = STACK_INIT_SIZE;
}

void Push(SqStack *s, ElemType e) {
	//如果栈满  追加空间
	if (s->top - s->base >= s->stackSize)
	{
		s->base = (ElemType *)realloc(s->base, (s->stackSize + STACKINCREMENT) * sizeof(ElemType));
		if (!s->base)
		{
			exit(0);
		}
		s->top = s->base + s->stackSize;  //设置栈顶
		s->stackSize = s->stackSize + STACKINCREMENT;
	}
	*(s->top) = e;
	s->top++;
}

void Pop(SqStack *s, ElemType *e) {
	if (s->top == s->base)
	{
		return;
	}
	*e = *--(s->top);
}

int StackLen(SqStack s) {
	return (s.top - s.base);
}

int main() {
	char cal[50];
	char c, e;
	SqStack s;
	initStack(&s);
	printf("请输入中缀表达式 输入#表示结束\n");
	scanf_s("%c", &c);
	while (c != '#')
	{
		while (c>='0' && c<='9')
		{
			printf("%c ", c);
			scanf_s("%c", &c);
			if (c<'0' || c>'9')
			{
				printf(" ");
			}
		}
		if (c == ')')
		{
			Pop(&s, &e);
			while (e != '(')
			{
				printf("%c ", e);
				Pop(&s, &e);
			}
		}
		else if (c == '+' || c == '-')
		{
			if (!StackLen(s))
			{
				Push(&s, c);
			}
			else {
				do
				{
					Pop(&s, &e);
					if (e == '(')
					{
						Push(&s, e);
					}
					else {
						printf("%c ", e);
					}
				} while (StackLen(s) && e!='(');
				Push(&s, c);
			}
		}else if (c=='*' || c=='/' || c=='(')
		{
			Push(&s, c);
		}else if (c=='#')
		{
			break;
		}
		else {
			printf("出错，输入格式错误");
			return -1;
		}
		scanf_s("%c", &c);
	}
	while (StackLen(s))
	{
		Pop(&s, &e);
		printf("%c ", e);
	}
	return 0;cd
}