Name format Lab

Question

C++ - I'm having a big problem with my code and I don't understand where I did the mistake because I'm not getting the result that I want for example the 1st output that problem is asking me :(

My FULL CODE

Outputs that I'm getting wrong

#include <iostream>
#include <string>
using namespace std;

int main() {

   string firstName, middleName, lastName, theName;
   
   getline(cin, theName);
   
   int findN = theName.find(" ");
   firstName = theName.substr(0, findN);
   int findN2 = theName.find(" ", findN + 1);
   if (findN2 != string::npos){
      middleName = theName.substr(findN2 + 1, findN2 - findN - 1);
      lastName = theName.substr(findN2 + 1, theName.length() - findN2 - 1);
      cout << lastName << ", " << firstName[0] << "." << middleName[0] << "." << endl;
      }
      else {
         lastName = theName.substr(findN + 1, theName.length() - findN - 1);
         cout << lastName << ", " << firstName[0] << " . " << endl;
         }
   

   return 0;
}

Okay I did edition to my post and now you can see my full code :D — Zahid, Oct 03 '20 at 00:42
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Wouldn't middle name be `middleName = theName.substr(findN + 1, findN2 - findN - 1);`? — David C. Rankin, Oct 03 '20 at 00:48

score 1 · Answer 1 · answered Oct 03 '20 at 00:48

1

I suggest learning to use debugger.

#include <iostream>
#include <string>
using namespace std;

int main() {

    string firstName, middleName, lastName, theName;

    getline(cin, theName);

    int findN = theName.find(" ");
    firstName = theName.substr(0, findN);
    int findN2 = theName.find(" ", findN + 1);
    if (findN2 != string::npos) {
       //changed from findN2 + 1 to findN + 1
        middleName = theName.substr(findN + 1, findN2 - findN - 1);
        lastName = theName.substr(findN2 + 1, theName.length() - findN2 - 1);
        cout << lastName << ", " << firstName[0] << "." << middleName[0] << "." << endl;
    }
    else {
        lastName = theName.substr(findN + 1, theName.length() - findN - 1);
                           //fixed the white space " . " -> ". "
        cout << lastName << ", " << firstName[0] << ". " << endl;
    }


    return 0;
}

answered Oct 03 '20 at 00:48

pesuww

105
11

Two suggestions. It is always worth mentioning [Why is “using namespace std;” considered bad practice?](https://stackoverflow.com/q/1452721/364696) and understanding the difference [C++: “std::endl” vs “\n”](https://stackoverflow.com/questions/213907/c-stdendl-vs-n). Actually 3 -- you should change `int` to `size_t` as that is the proper type for the return of `.find()` and eliminates the warning of comparison between signed and unsigned types with `findN2 != string::npos`. – David C. Rankin Oct 03 '20 at 00:58
Good points. I didn't want to edit the code too much so I just decided to stick with the minimal changes. – pesuww Oct 03 '20 at 01:01
Yes, it's always a balance to strike between helping with the exact issue,and pointing out additional improvements. That's why it may be something you just mention or drop in a footnote. What you are trying to overcome is there are some very bad C++ instructors out there that may think comparing `int` and `size_t` is just fine, etc.. Always try to ensure the questioner comes away pointed in the right direction. These comments will suffice for this question. – David C. Rankin Oct 03 '20 at 01:05

score 0 · Answer 2 · answered Oct 03 '20 at 00:56

0

This is easily solved with debugger.

If there is a second space, both of your middleName and middleName are assigned substring starting from findN2 + 1.

If there is no second space, you have extra spaces around . here: " . "

answered Oct 03 '20 at 00:56

Vlad Feinstein

10,960
1
12
27

Name format Lab

2 Answers2