67求调

#include<bits/stdc++.h>
using namespace std;
string s;
stack<double> stk; 
int main()
{
	int num=0; 
	getline(cin,s);
	for(int i=0;i<s.size();i++)
	{
		if(s[i]=='@')
		{
			break;  
		}
		else if(s[i]>='0' && s[i]<='9')
		{
			num=num*10+(s[i]-'0');
		}
		else if(s[i]=='.')
		{
			stk.push(num);
			num=0;
		}
		else
		{
			int num1=stk.top();   
			stk.pop();   
			int num2=stk.top();  
			stk.pop();  
			if(s[i]=='+')
			{
				stk.push(num1+num2);
			}	
			if(s[i]=='-')
			{
				stk.push(num2-num1);
			}	
			if(s[i]=='*')
			{
				stk.push(num1*num2);
			}
			if(s[i]=='/')
			{
				stk.push(num1/num2);
			}
		} 
	}
	cout<<stk.top();  
}