Stack calculator

I want make a Stack calculator.

My code is

#ifndef STACK_H

#define STACK_H

#include

#include

#include

template

class Stack

{

public:

// Default constructor

Stack(){

capacity = 10;

top = -1;

array = new type[capacity];

};

// Destructor

~Stack();

// Return top element of stack

type& Top();

void Push(const type& item);

void Pop();

bool IsEmpty() const;

void Print() {

for(int i=0; i<=top; i++) std::cout << array[i] << std::endl;

};

type getpop();

int Size() { return top+1; }

private:

// Data

type *array;

int capacity;

int top;

};

#ifndef STACK_TXX

#define STACK_TXX

#include "stack.txx"

#endif

#endif

stack.txx

template

Stack::~Stack()

{

delete [] array;

}

template

type& Stack::Top()

{

if(top < 0) assert(false);

return array[top];

}

template

void Stack::Push(const type& item)

{

if(top == capacity-1) // double capacity

{

type* temp = new type[capacity*2];

for(int i=0; i

{

temp[i] = array[i];

}

type* ret = array;

array = temp;

delete [] ret;

capacity *= 2;

}

array[ ++top ] = item;

}

template

void Stack::Pop()

{

if(top >= 0) top--;

}

template

bool Stack::IsEmpty() const

{

if(top < 0) return true;

else return false;

}

My main calculator.h

#ifndef CALCULATOR_H

#define CALCULATOR_H

#include "stack.h"

#include "string"

#include

#include

template

type Stack::getpop()

{

if(!IsEmpty())

return array[top--];

}

bool isoperator(char ch)

{

if(ch == '+' || ch == '-' || ch == '*' || ch == '/')

return true;

else

return false;

}

bool number(char n)

{

if(n >= '0' && n <= '9')

return true;

else

return false;

}

int order(char a)

{

switch(a)

{

case '+':

case '-':

return 1;

case '*':

case '/':

return 2;

default:

return 0;

}

}

void Postfix(char* st, char* oper)

{

char* result;

Stack stacks;

char a;

int i =0, j=0, top=0;

for(; st[i]!='\0'; i++)

{

a=st[i];

if(a=='(')

{

stacks.Push(a);

i++;

}

else if(a==')')

{

while(!stacks.IsEmpty()&&stacks.Top()!='(')

{

oper[j++] = stacks.getpop();

}

stacks.Pop();

i++;

}

else if(isoperator(a))

{

while(!stacks.IsEmpty()&&order(stacks.Top())>=order(a))

{

oper[j++] = stacks.getpop();

}

stacks.Push(a);

}

else

{

oper[j++]=a;

}

while(top > 0)

{

oper[j++] = stacks.getpop();

top--;

}

int k =0;

while(!stacks.IsEmpty())

{

st[k]=stacks.Top();

stacks.Pop();

}

}

while(!stacks.IsEmpty())

{

result += stacks.getpop();

}

}

float calculator(char a, double b, double c)

{

switch(a)

{

case '+': return b + c;

case '-': return b - c;

case '*': return b * c;

case '/': return b / c;

}

}

double Eval(char* in)

{

char* oper;

Postfix(in, oper);

char temp[2];

int p=0, q=0;

for(; oper[p]!= '\0'; p++)

{

switch(oper[p])

{

case '+':

case '-':

case '*':

case '/':

in[q-1]=calculator(oper[p],in[q-1],in[q]);

q--;

break;

default:

temp[0] = temp[p];

in[++q] = atof(temp);

}

}

return in[q];

}

#endif

I want to make right code for calculator.h

But, it outs segementation fault.

Change my code please.

And stack.h and stack.txx can't change