#include<bits/stdc++.h> using namespace std; int i=0,ii=0,ans=0,bl=0; int dj=0; char l[100],bianliang[10],bianlinag2[10]; void jia(int x){ if(l[x]'+'){ l[x-1]=l[x]+l[x-1]; } else {return ;} return ; } void jian(int x){ if(l[x]'-'){ l[x-1]=l[x-1]-l[x]; } else {return ;} return ; } void jiabian(int x){ if(l[x]'+'){ l[x-1]=l[x-1]-l[x]; } else {return ;} return ; } void jianbian(int x){ if(l[x]'-'){ l[x-1]=l[x]+l[x-1]; } else {return ;} return ; } int main(){ while(cin>>l[i]&&l[i]!=EOF){i++;} for(i>=0;i--;){ if(l[i]>=97&&l[i]<=122){ int l1=i; while(l[l1]!='+'){

bianliang[ii]=l[l1];
				l1=l1--;
				ii++;
				if(l[l1]=='-'){
					bianliang[ii]=l[l1];
					break;
				}
			}
			continue;
		}//存变量 
		if(l[i]=='='){
			jiabian(i);
			jianbian(i);	
		}
		else{
		jia(i);
		jian(i);
		}
	}
for(int j=ii;j>=0;j--){
	bianlinag2[dj]=bianliang[j];
	dj++;
}
for(int j=0;j<=dj-2;j++){
	bl=bl+bianlinag2[j];
}
ans=l[i]/bl;
cout<<bianlinag2[dj-1]<<"=";
printf(".3f",ans); 
return 0;

}