void main()
{ SElemType e;
SqStack *Sa;
clrscr();
cout<<"stackmain.cpp运行结果:\n";
Sa->InitStack(&Sa);
strcpy(e.name,"stu1");
strcpy(e.stuno,"100001");
e.age=20;
e.score=87;
cout<<"现在栈是空栈!\n";
cout<<"现在调用压栈函数!\n";
Sa->Push(e);
cout<<"现在栈有一个元素!\n";
StackPrintElem(&Sa->GetTop());
if(Sa->StackEmpty()) cout<<"栈Sa空!\n";
else cout<<"栈Sa非空!\n";
strcpy(e.name,"stu3");
strcpy(e.stuno,"100002");
e.age=21;
e.score=90;
Sa->Push(e);
cout<<"现在栈有二个元素!\n";
StackPrintElem(&e);
cout<<"栈Sa的长度:"<<Sa->StackLength()<<endl;
cout<<"现在将元素e弹出栈!\n";
Sa->Pop(&e);
StackPrintElem(&e);
cout<<"栈的剩余元素:\n";
Sa->StackTraverse(StackPrintElem);
if(Sa->StackEmpty()) cout<<"栈Sa空!\n";
else cout<<"栈Sa非空!\n";
getch();
}
double EvaExpression()
{
SqStack<int> OPTR;
SqStack<double> OPND;
int buffer;
bool preIsDigit = false;
bool hasDot = false;
int exp;
double ans = 0;
OPTR.Push(Index('#'));
buffer = mGetchar();
if (buffer == INPUT_VALID) return EvaExpression();
while (buffer!='#' || OPTR.GetTop()!=Index('#'))
{
if (buffer == '.')
{
if (hasDot)
{
char tmp_s[1024];
printf("您的输入有误，请确保输入的算术表达式合法！\n");
if (buffer != '\n') gets(tmp_s);
return EvaExpression();
}
hasDot = true;
exp = 0;
buffer = mGetchar();
if (buffer == INPUT_VALID) return EvaExpression();
}
else if (In(buffer, DIGIT))
{
if (preIsDigit)
{
double number;
OPND.Pop(&number);
if (hasDot)
{
exp--;
number += E(buffer-'0', exp);
}
else
{
number *= 10;
number += buffer-'0';
}
OPND.Push(number);
}
else
{
OPND.Push(buffer-'0');
preIsDigit = true;
}
buffer = mGetchar();
if (buffer == INPUT_VALID) return EvaExpression();
}
else
{
int toOperate, top;
preIsDigit = false;
hasDot = false;
toOperate = Index(buffer);
top = OPTR.GetTop();
switch(cmp[top][toOperate])
{
case -1:
OPTR.Push(toOperate);
buffer = mGetchar();
if (buffer == INPUT_VALID) return EvaExpression();
break;
case 0:
int tmp;
OPTR.Pop(&tmp);
buffer = mGetchar();
if (buffer == INPUT_VALID) return EvaExpression();
break;
case 1:
int op;
double a, b;
if (OPTR.Pop(&op) != OK || OPND.Pop(&b) != OK || OPND.Pop(&a) != OK)
{
char tmp_s[1024];
printf("您的输入有误，请确保输入的算术表达式合法！\n");
if (buffer != '\n') gets(tmp_s);
return EvaExpression();
}
ans = Operate(a, op, b);
OPND.Push(ans);
break;
case ERROR:
char tmp_s[1024];
printf("您的输入有误，请确保输入的算术表达式合法！\n");
if (buffer != '\n') gets(tmp_s);
return EvaExpression();
default:
exit(ERROR);
}
}
}
OPND.Pop(&ans);
if (OPTR.IsEmpty() || OPND.IsEmpty() ) return ans;
char tmp_s[1024];
printf("您的输入有误，请确保输入的算术表达式合法！\n");
if (buffer != '\n') gets(tmp_s);
return EvaExpression();
}