#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cmath>
#include<cctype>
#include<math.h>
#include<string>
#include<string.h>
#include<stack>
#include<queue>
#include<vector>
#include<utility>
#include<set>
#include<map>
#include<stdlib.h>
#include<iomanip>

using namespace std;

#define ll long long
#define ld long double
#define EPS 0.0000000001
#define INF 1e9
#define LINF (ll)INF*INF
#define MOD 1000000007
#define rep(i,n) for(int i=0;i<(n);i++)
#define loop(i,a,n) for(int i=a;i<(n);i++)
#define all(in) in.begin(),in.end()
#define shosu(x) fixed<<setprecision(x)

#define int ll //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

typedef vector<int> vi;
typedef vector<string> vs;
typedef pair<int,int> pii;
typedef vector<pii> vp;

int gcd(int a, int b){
    if(b==0) return a;
    return gcd(b,a%b);
}
int lcm(int a, int b){
    return a/gcd(a,b)*b;
}


signed main(void) {
    string s;
    while(getline(cin,s)){
        s += " ";
        stack<double> st;
        int num = 0;
        bool c = false;
        rep(i,s.size()){
            if(s[i] == '-' && isdigit(s[i+1])){
                c = true;
            }else if(isdigit(s[i])){
                num *= 10;
                num += s[i]-'0';
            }else if(s[i] == ' '){
                i--;
                if(isdigit(s[i])){
                    if(c)num = -num;
                    //cout << " " << num << endl;
                    st.push(num);
                    num = 0;
                    c = false;
                }else{
                    double a = st.top();
                    st.pop();
                    double b = st.top();
                    st.pop();
                    if(s[i] == '+')st.push(b+a);
                    if(s[i] == '-')st.push(b-a);
                    if(s[i] == '*')st.push(b*a);
                    if(s[i] == '/')st.push(b/a);
                }
                i++;
                //cout << st.top() << endl;
            }
        }
        cout << shosu(10) << st.top() << endl;
    }

}

