Untitled

class Solution {
public:
    int getNum(string& str, int i, int j){
        int res= 0;
        for(int p=i;p<=j;p++){
            res*=10;
            res+= (str[p]-'0');
        }
        return res;
    }

    int calculate(string& str, int i, int left, int right){
        if(str[i]=='-') return left- right;
        else if(str[i]=='+') return left+ right;
        else if(str[i]=='*') return left* right;
        else return left/right;
    }


    vector<int> solve(string& str, int i, int ss){
        vector<int> res;
        if(i>=ss) return res;
        int operatorIndex= -1;
        int lastNum= -1;
        int st= i;
        for(int p= i;p<ss;p++){
            if(str[p]<='9' && str[p]>='0') continue;

            if (str[p] == '+' || str[p] == '-' || str[p] == '*' || str[p] == '/' ){
                if(operatorIndex ==-1)
                    lastNum= getNum(str, st, p-1);
                else{
                    lastNum = calculate(str, operatorIndex, lastNum, getNum(str, st, p-1));
                }

                
                operatorIndex= p;
                st= p+1;
            }

            vector<int> auxRes= solve(str, p+1, ss);
            for(auto resValue: auxRes){
                res.push_back(calculate(str, operatorIndex, lastNum, resValue));
            }

        }

        if(operatorIndex == -1)res.push_back(getNum(str, st, ss-1));
        else res.push_back(calculate(str, operatorIndex,lastNum, getNum(str, st, ss-1)));
        
        return res;
    }
    
    
    vector<int> diffWaysToCompute(string expression) {
        int ss= expression.size();
        return solve(expression, 0,ss);
    }
};