和题解挺像的但是本地也都是0

#include<bits/stdc++.h>
using namespace std;
stack <int> c;
string s;
int main() {
    cin>>s;
    for(int i=0;i<s.length();i++){
        int n=0;
        if(s[i]=='@') break;

        else if(s[i]>='0'&&s[i]<='9'){
            if(n!=0){
                n=n*10+s[i]-48;
            }
            else n=s[i]-48;
        }

        else if(s[i]=='.'){
            c.push(n);
            n=0;
        } 

        else{
            int x=c.top();
            c.pop();
            int y=c.top();
            c.pop();
            if(s[i]=='+') c.push(x+y);
            if(s[i]=='-') c.push(y-x);
            if(s[i]=='*') c.push(x*y);
            if(s[i]=='/') c.push(y/x);
        }

    }

    cout<<c.top();

    return 0;
}