```cpp
#include <bits/stdc++.h>
using namespace std;
long long c1[100005];
int main()
{
long long i=0,top=0;
char ch;
while((ch=getchar())!='@')
{
if(ch>='0'&&ch<='9')
{
top*=10;
top+=ch-'0';
}
else if(ch=='.')
{
c1[++i]=top;
top=0;
}
else if(ch=='+')
{
c1[i-1]=c1[i-1]+c1[i];
c1[i]=0;
i--;
}
else if(ch=='-')
{
c1[i-1]=c1[i-1]-c1[i];
c1[i]=0;
i--;
}
else if(ch=='*')
{
c1[i-1]=c1[i-1]*c1[i];
c1[i]=0;
i--;
}
else if(ch=='/')
{
c1[i-1]=c1[i-1]/c1[i];
c1[i]=0;
i--;
}
}
cout<<c1[1];
return 0;
}
```
by Kisaragi_167 @ 2019-02-27 21:08:27