#include <bits/stdc++.h>

using namespace std;

struct num
{
    bool isUnknown = false;
    int N;

    string toString(){
        stringstream ss;
        ss<<N;
        if(isUnknown){
            ss<<"x";
        }
        return ss.str();
    }
};

vector<char> v,vl,vr;
vector<num> nl,nr;
char unknownC;




int main(){
    char c;
    while (scanf("%c",&c)!=EOF)
    {
        v.push_back(c);
    }
    for(int i = 0;i<v.size();i++){
        if(v[i]=='='){
            for(int j = i + 1;j<v.size();j++){
                if(j == i + 1 &&v[j]!='-'){
                    vl.push_back('+');
                }
                vr.push_back(v[j]);
            }
            break;
        }
        if(i == 0 &&v[i]!='-'){
            vl.push_back('+');
        }
        vl.push_back(v[i]);
    }
    bool isFu = false;
    vector<int> numBuffer;
    for(int i = 0;i<vl.size();i++){
        num n;
        char curC = vl[i];
        //cout<<"AT:"<<i;
        if(curC == '-'){
            int curN = 0;
            int K = 1;
            for(int j = numBuffer.size()-1;j>=0;j--){
                curN += (numBuffer[j]*K);
                K*=10;
            }
            if(isFu == true){
                curN *= -1;
            }
            n.N = curN;
            if(n.N != 0){
                nl.push_back(n);
            }
            isFu = true;
            numBuffer.clear();
        }
        else if(curC == '+'){
            int curN = 0;
            int K = 1;
            for(int j = numBuffer.size()-1;j>=0;j--){
                curN += (numBuffer[j]*K);
                K*=10;
            }
            if(isFu == true){
                curN *= -1;
            }
          
            n.N = curN;
            if(n.N != 0){
                nl.push_back(n);
            }
            isFu = false;
            numBuffer.clear();
            //cout<<"Start R";
        }
        else if(curC >= '0' && curC <= '9'){
            numBuffer.push_back(curC - '0');
        }
        else if(curC >= 'a'&&curC<='z'){
            //cout<<"Find Unk:"<<curC<<endl;
            unknownC = curC;
            int curN = 0;
            int K = 1;
            for(int j = numBuffer.size()-1;j>=0;j--){
                curN += (numBuffer[j]*K);
                K*=10;
            }
            if(isFu == true){
                curN *= -1;
            }
            n.N = curN;
            if(n.N == 0){
                n.N = 1;
            }
            n.isUnknown = true;
            if(n.N != 0){
                //cout<<"Push Unk:"<<nl.size()<<endl;
                nl.push_back(n);
            }
            numBuffer.clear();
        }
        if(i == vl.size()-1){
            int curN = 0;
            int K = 1;
            for(int j = numBuffer.size()-1;j>=0;j--){
                curN += (numBuffer[j]*K);
                K*=10;
            }
            if(isFu == true){
                curN *= -1;
            }
          
            n.N = curN;
            if(n.N != 0){
                nl.push_back(n);
            }
            numBuffer.clear();
            break;
        }
    }
    //Read Right
    isFu = false;
    numBuffer.clear();
    for(int i = 0;i<vr.size();i++){
        num n;
        char curC = vr[i];
        //cout<<"AT:"<<i;
        if(curC == '-'){
            int curN = 0;
            int K = 1;
            for(int j = numBuffer.size()-1;j>=0;j--){
                curN += (numBuffer[j]*K);
                K*=10;
            }
            if(isFu == true){
                curN *= -1;
            }
            n.N = curN;
            if(n.N != 0){
                nr.push_back(n);
            }
            isFu = true;
            numBuffer.clear();
        }
        else if(curC == '+'){
            int curN = 0;
            int K = 1;
            for(int j = numBuffer.size()-1;j>=0;j--){
                curN += (numBuffer[j]*K);
                K*=10;
            }
            if(isFu == true){
                curN *= -1;
            }
          
            n.N = curN;
            if(n.N != 0){
                nr.push_back(n);
            }
            isFu = false;
            numBuffer.clear();
            //cout<<"Start R";
        }
        else if(curC >= '0' && curC <= '9'){
            numBuffer.push_back(curC - '0');
        }
        else if(curC >= 'a'&&curC<='z'){
            unknownC = curC;
            //cout<<"Find Unk:"<<curC<<endl;
            int curN = 0;
            int K = 1;
            for(int j = numBuffer.size()-1;j>=0;j--){
                curN += (numBuffer[j]*K);
                K*=10;
            }
            if(isFu == true){
                curN *= -1;
            }
            n.N = curN;
            if(n.N == 0){
                n.N = 1;
            }
            n.isUnknown = true;
            if(n.N != 0){
                //cout<<"Push Unk:"<<nl.size()<<endl;
                nr.push_back(n);
            }
            numBuffer.clear();
        }
        if(i == vr.size()-1){
            int curN = 0;
            int K = 1;
            for(int j = numBuffer.size()-1;j>=0;j--){
                curN += (numBuffer[j]*K);
                K*=10;
            }
            if(isFu == true){
                curN *= -1;
            }
          
            n.N = curN;
            if(n.N != 0){
                nr.push_back(n);
            }
            numBuffer.clear();
            break;
        }
    }
    //cout<<vl[1];
    //cout<<nr[0].toString();

    //Move All unknown to left

    float unknownXi = 0;
    float Sum = 0;
    for(int i = 0;i<nl.size();i++){
        if(nl[i].isUnknown){
            unknownXi += (float)nl[i].N;
        }
    }
    for(int i = 0;i<nr.size();i++){
        if(nr[i].isUnknown){
            unknownXi -= (float)nr[i].N;
        }
    }
    for(int i = 0;i<nl.size();i++){
        if(!nl[i].isUnknown){
            Sum -= (float)nl[i].N;
            //cout<<"Cut:"<<nl[i].N<<endl;
        }
    }
    for(int i = 0;i<nr.size();i++){
        if(!nr[i].isUnknown){
            Sum += (float)nr[i].N;
            //cout<<"Add:"<<nr[i].N<<endl;
        }
    }
    float ans = (Sum/unknownXi);
    //cout<<unknownXi;
    //cout<<ans;
    cout<<unknownC<<"=";
    printf("%.3f",ans);
}