#include<bits/stdc++.h>
using namespace std;
int main(){
    int a=1,b=1,n=0,s1=0,s2=0;
    char op,z;
    while((z=getchar())!=EOF)
    {
        if(z>='0'&&z<='9')
        {
            n=n*10+z-'0';
        }
        else if(z>='a'&&z<='z')
        {
            op=z;
            if(n==0)n==1;
            s1+=a*b*n;
            n=0;
        }
        else
        {
            s2+=a*b*n;
            n=0,a=1;
            if(z=='-')a=-1;
            if(z=='=')b=-1;
        }
    }
    printf("%c=%.3lf",op,-(double)s2/s1);
    return 0;
}