#include<iostream>
#include<stdio.h>
#include<conio.h>
#include<string.h>
#include<math.h>
using namespace std;
class stack
{
public:
int s[20],res;
double op1,op2;
int top;
char postfix[20],symbol;
stack()
{
top=-1;
}
void evaluation()
{ cout<<"enter the valid postfix expression \n";
cin>>postfix;
for(int i=0;i<strlen(postfix);i++)
{
symbol=postfix[i];
if(isdigit(symbol))
s[++top]=symbol-'0'; 
else
{
op2=s[top--]; 
op1=s[top--];
res=op(symbol,op1,op2);
s[++top]=res; 
}
}
res=s[top--];  
cout<< "Evaluation result of the postfix expression= \n";
cout<<res<<endl;
}
double op(char symbol,double op1,double op2)
{
switch(symbol)
{
case '+':return op1+op2;
case '-':return op1-op2;
case '*':return op1*op2;
case '/': return op1/op2;
case '^':
case '$': return pow(op1, op2);
}
} };
int main()
{
stack obj;
obj.evaluation();
getch();
return 0;
}