#include<bits/stdc++.h>
using namespace std;
int main(){
	int ans=0,sum=0;
	string a={};
	cin>>a;
	int len=a.size();
	len--;
	int len1=0;
	while(a[len1]!='=') len1++;
	len1--;
	int strat=len1+2;
	if(a[0]=='-'){
		int i=1;
		if(a[i]>='a'&&a[i]<='z') ans++,i++;
		else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans+=a[i]-'0',i+=2;
		else sum+=a[i]-'0',i++;
		for(;i<=len1;){
			if(a[i]=='-'){
				i++;
				if(a[i]>='a'&&a[i]<='z') ans++,i++;
				else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans+=a[i]-'0',i+=2;
				else sum+=a[i]-'0',i++;
			}
			else{
				i++;
				if(a[i]>='a'&&a[i]<='z') ans++,i++;
				else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans+=a[i]-'0',i+=2;
				else sum-=a[i]-'0',i++;
			}
		}
	}
	else{
		int i=0;
		if(a[i]>='a'&&a[i]<='z') ans++,i++;
		else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans+=a[i]-'0',i+=2;
		else sum+=a[i]-'0',i++;
		for(;i<=len1;){
			if(a[i]=='-'){
				i++;
				if(a[i]>='a'&&a[i]<='z') ans++,i++;
				else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans+=a[i]-'0',i+=2;
				else sum+=a[i]-'0',i++;
			}
			else{
				i++;
				if(a[i]>='a'&&a[i]<='z') ans++,i++;
				else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans+=a[i]-'0',i+=2;
				else sum-=a[i]-'0',i++;
			}
		}
	}
	int sum1=0,ans1=0;
	if(a[0]=='-'){
		int i=strat;
		if(a[i]>='a'&&a[i]<='z') ans1++,i+=2;
		else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans1+=a[i]-'0',i+=3;
		else sum1+=a[i]-'0',i+=2;
		for(;i<=len;){
			if(a[i]=='-'){
				i++;
				if(a[i]>='a'&&a[i]<='z') ans1++,i++;
				else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans1+=a[i]-'0',i+=2;
				else sum1+=a[i]-'0',i++;
			}
			else{
				i++;
				if(a[i]>='a'&&a[i]<='z') ans1++,i++;
				else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans1+=a[i]-'0',i+=2;
				else sum1-=a[i]-'0',i++;
			}
		}
	}
	else{
		int i=strat;
		if(a[i]>='a'&&a[i]<='z') ans1++,i+=1;
		else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans1+=a[i]-'0',i+=2;
		else sum1+=a[i]-'0',i++;
		for(;i<=len;){
			if(a[i]=='-'){
				i++;
				if(a[i]>='a'&&a[i]<='z') ans1++,i++;
				else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans1+=a[i]-'0',i+=2;
				else sum1+=a[i]-'0',i+=1;
			}
			else{
				i++;
				if(a[i]>='a'&&a[i]<='z') ans1++,i++;
				else if(a[i]>='0'&&a[i]<='9'&&a[i+1]>='a'&&a[i+1]<='z') ans1+=a[i]-'0',i+=2;
				else sum1-=a[i]-'0',i++;
			}
		}
	}
	int t=0;
	while(a[t]!='a') t++;
	cout<<a[t]<<"="<<fixed<<setprecision(3)<<(sum*1.00+sum1*1.00)/(ans*1.00+ans1*1.00)*1.00;
	return 0;
}

前4个WA了，救救蒻尐吧！！！！！！