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In the program I'm working on, I use std::getline twice in order for the user to enter two inputs relating to different attributes of a person: their name, and then their partisan identification. The program then asks the user if they want to include additional people, and if the user indicates that they do, it presents the prompts to the user again. My program works for the first person the user enters these attributes for. However, if I indicate that I want to add another person, the program "skips over" the first prompt, displaying the question but not actually allowing the user to add input. It also displays the second prompt at the same time, allowing me to respond to that prompt but not the first one. This problem repeats for each successive person I try to enter attributes for.

Image of the problem I described

I tried fixing this by including cin.ignore(100, 'n') at the end of my program, but that simply causes the program to stop functioning after I enter the first person's name and partisan identification and ask to enter attributes for more people. The program still runs but does not prompt me again as it should.

Here is my code:

// DelibDem.cpp : Defines the entry point for the application.
//

#include "DelibDem.h"
#include <stdio.h>
#include <vector>

//initializing variables
using namespace std;
bool continue_ = true;
string name = "";
string partyID = "";
int numD = 0;
int numR = 0;
int difference = 0;
int vectorSize = 0;
int newVectorSize = 0;
struct person{
    string Name;
    string PartyID;
    string equivalentName;
    string equivalenceClass;
};
vector<person> Sample;

int main()
{
    //user adds people to the vector. I have not yet implemented the code that actually adds the people specified by the user yet, because I am still trying
    //to figure out why my getline code is not working.
    while (continue_ == true) {
        string personName;
        string personPartyID;
        string answer;
        person inputtedPerson;
        cout << "Enter a person's name: ";
        std::getline(cin, personName);
        cout << "Enter the person's party ID (D or R): ";
        std::getline(cin, personPartyID);
        if (personPartyID == "D") person inputtedPerson = { personName, personPartyID, "", "Republicans" };
        else person inputtedPerson = { personName, personPartyID, "", "Democrats" };
        cout << "Do you wish to add more people? (Y/N) ";
        cin >> answer;
        if (answer == "N") continue_ = false;
    }
    //The number of Democrats in the sample is stored in numD. The number of Republicans is stored in numR.
    for (auto& element : Sample)
    {
        if (element.PartyID == "D") numD++;
        else numR++;
    }
    //print the number of Democrats and Republicans
    cout << numD;
    cout << numR;
    //print the properties of each element in the sample
    for (auto& element : Sample)
    {
        cout << element.Name << endl;
        cout << element.PartyID << endl;
        cout << element.equivalentName << endl;
        cout << element.equivalenceClass << endl;
        cout << "\n";
    }
    return 0;
}
StanAtkinson
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    Welcome to Stack Overflow. Please read [the help pages](http://stackoverflow.com/help), take the SO [tour], read [ask], as well as [this question checklist](https://codeblog.jonskeet.uk/2012/11/24/stack-overflow-question-checklist/). Then please create a [mre] and [edit] your question to show it. And copy-paste the output *as text* into your question, [don't show images of text](https://meta.stackoverflow.com/questions/285551/why-should-i-not-upload-images-of-code-data-errors-when-asking-a-question). – Some programmer dude Dec 02 '22 at 05:02
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    You will probably have to show some code if the problem is not this: [https://stackoverflow.com/questions/21567291/why-does-stdgetline-skip-input-after-a-formatted-extraction](https://stackoverflow.com/questions/21567291/why-does-stdgetline-skip-input-after-a-formatted-extraction) – drescherjm Dec 02 '22 at 05:04
  • @drescherjm My apologies. I forgot to include my code initially. I have included it now. – StanAtkinson Dec 02 '22 at 05:10
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    your last `cin >> answer`left the CR still pending, use getline instead – pm100 Dec 02 '22 at 05:13
  • OK, I've fixed the problem now by placing cin.ignore() - with no parameters - at the end of my while loop. Thanks for the help anyway, drescherjm and pm100! – StanAtkinson Dec 02 '22 at 05:21
  • *cin.ignore() - with no parameters* May not be good enough. a particularly inept or malicious user could type a space and then hit enter. `ignore` will only eat one of those characters, the space, leaving the newline. – user4581301 Dec 02 '22 at 05:37
  • If you check [this `ignore` reference](https://en.cppreference.com/w/cpp/io/basic_istream/ignore) it uses `ignore(max_size, '\n')` where `max_size` is `constexpr auto max_size = std::numeric_limits::max();`. – Some programmer dude Dec 02 '22 at 07:00

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