evualation of postfix expression

[azmizryk]

hello programmers i need help to solve this i write a code that solve the Postfix Expression but there are two problems...if there is 22 in my expression the code treated is as 2,2 and produce a result similarly if there is a number 2.2 in expression the code break it in this form 2,.,2... u can see this and can be easily understand what i want say...

#include<iostream>
#include<conio.h>
#include"stack1.cpp"
#include<string>
using namespace std;
void main()
{
	stack s;
	float p1,p2,res=0;
	char string[20];
	cout<<"Enter the postfix expression..";
	cin.getline(string,20);
	for(int i=0;string[i]!='\0';i++)
	{
		if(string[i]>='0' && string[i]<='9')
			s.push((float)string[i]-'0');
		else
		{
			p2=s.pop();
			p1=s.pop();
			if(string[i]=='+')
				res=p1+p2;
			else if(string[i]=='-')
				res=p1-p2;
			else if(string[i]=='*')
				res=p1*p2;
			else if(string[i]=='/')
				res=p1/p2;
			else if(string[i]=='$')
			{	res=1;
				for(int n=1;n<=p2;n++)
					res=res*p1;
			}
			s.push(res);
		}
	}
	cout<<"\nResult is:"<<s.pop();
	getch();
}

[azmizryk]

i there any help????

[tfityo]

You can use a flag indicating if the last character was a number or symbol:

		if(string[i]>='0' && string[i]<='9'){
                        if (fNumber)
                            s.push(s.pop()*10 + (float)string[i]-'0');
                       else{
                            fNumber = true;
			    s.push((float)string[i]-'0');
                      }
                }
		else
		{
                       fNumber = false;