#include <iostream>
#include<cstring>
using namespace std;
int const MAX = 100;

class Stack
{
private:
	double *arr;
	int top;
	int Size;
	bool full() const;


public:

	Stack();
	Stack(Stack const&);
	~Stack();
	Stack& operator=(Stack const &);
	bool Empty() const;
	double peek() const;
	void push(double);
	double pop();

};




Stack::Stack()
{
	Size = MAX;
	arr = new double[Size];
	top = -1;
}

Stack::Stack(Stack const& s) : Size(s.Size), top(s.top)
{
	arr = new double[Size];
	for (int i = 0; i <= top; i++)
		arr[i] = s.arr[i];
}

Stack& Stack::operator=(Stack const& s) {
	if (this != &s) {
		Size = s.Size;
		top = s.top;
		delete[] arr;
		arr = new double[Size];
		for (int i = 0; i <= top; i++)
			arr[i] = s.arr[i];
	}
	return *this;
}


Stack::~Stack()
{
	delete[] arr;
}

bool Stack::Empty() const
{
	return top == -1;
}

double Stack::peek() const
{
	if (Empty()) {
		cout << "You try to read from empty stack!\n";
		return 0;
	}

	return arr[top];
}

void Stack::push(double x) {
	if (full()) {
		cout << "The stack is full. You can push only 100 doubles!/n";
	}
	arr[++top] = x;
}

bool Stack::full() const {
	return top == Size - 1;
}

double Stack::pop() {
	if (Empty()) {
		cout << "You try to delete form empty stack!\n";
		return 0;
	}
	return arr[top--];
}


//#include<iostream>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
int MaxSize = 100;
double PRNcalc(char arr[])
{


    //std::cout<<"Niza e :"<<arr<<std::endl;

    char* buffer;
    double n;
    double d;
    int k=0;
	int Size = 100;
	//arr = new char[size];
	buffer = new char[Size];
	Stack NewSteak;
		char in;


        n = atof(buffer);
		for (int i = 0; i < strlen(arr); i++)
		{
			in = arr[i];
			//std::cout<<arr[i];

				buffer[k] = arr[i];
				k++;
if (in == '+') {
				double a = NewSteak.peek();
				NewSteak.pop();
				double b = NewSteak.peek();
				NewSteak.pop();
				NewSteak.push(a + b);

			}
			else if (in == '-') {
				double a = NewSteak.peek();
				NewSteak.pop();
				double b = NewSteak.peek();
				NewSteak.pop();
				NewSteak.push(a - b);

			}
			else if (in == '*') {
				double a = NewSteak.peek();
				NewSteak.pop();
				double b = NewSteak.peek();
				NewSteak.pop();
				NewSteak.push(a * b);
			}
			else if (in == '/') {
				double a = NewSteak.peek();
				NewSteak.pop();
				double b = NewSteak.peek();
				NewSteak.pop();
				NewSteak.push(a / b);}
			if (isspace(in))
			{

			     if (in == '+') {
				double a = NewSteak.peek();
				NewSteak.pop();
				double b = NewSteak.peek();
				NewSteak.pop();
				NewSteak.push(a + b);

			}
			else if (in == '-') {
				double a = NewSteak.peek();
				NewSteak.pop();
				double b = NewSteak.peek();
				NewSteak.pop();
				NewSteak.push(a - b);

			}
			else if (in == '*') {
				double a = NewSteak.peek();
				NewSteak.pop();
				double b = NewSteak.peek();
				NewSteak.pop();
				NewSteak.push(a * b);
			}
			else if (in == '/') {
				double a = NewSteak.peek();
				NewSteak.pop();
				double b = NewSteak.peek();
				NewSteak.pop();
				NewSteak.push(a / b);

			}
			else {

				n = atof(buffer);

				NewSteak.push(n);

				delete[] buffer;
				k=0;
				buffer = new char[Size];

			}}


	}
	d = NewSteak.peek();
	return d;
}
int main()
{
    double PRNcalc(char arr[]);
	char arr[MAX];
    std::cout << "Enter the notation"<<std::endl;

	std::cin.getline(arr,100);

	std::cout<<"\nRESULT:"<<PRNcalc(arr);

	return 0;
}