Precautions for using stoi function

     Appeared when writing questions bug, After many times of debugging , Only to find out is stoi There are some things you don't pay attention to when using the function .

int main()
{
    
    string s = "";
    cout << stoi(s);
    return 0;
}

     Similar to the code above ,s Is an empty string , perhaps s There are not all numeric characters in , There will be running errors .

     therefore stoi When using, the parameter string must be numeric characters . Here again write the following code .

int main()
{
    
    string s;
    cin >> s;
    vector<int> record;
    istringstream is(s);
    string add;
    while(getline(is, add, '.')) record.push_back(stoi(add));
    for(int i = 0; i < record.size(); i++)
    {
    
       cout << record[i] << endl;   
    }
    return 0;
}

 Input ：
12..23
 Output ：
 Report errors 

     According to the previous stoi The use of logic , while(getline(is, add, ‘.’) The second string read should be an empty string , Should not call stoi, Why do you report errors , This problem is of the same kind .