CODEWITHSUNDEEP
c++
Ahmed Abdelaal
Ahmed Abdelaal

Reputation: 15

Getline & cin.ignore in c++

I know there are similar questions to mine, but I checked alot of them and didn't find the answer so I hope someone can help me. So what I am trying to do is store some strings into arrays, but some of these strings could consist of more than one word, so I searched the internet and found out I have to use cin.ignore() and getline. I used them, as seen in my code below, but the error happens in the second and third string where the first letter of surname[0] and address[0] is removed. So why is that?

Here is my code:

int size;
cout<<"Please enter the number of entries"<<endl;
cin>>size;
cin.ignore();
string* firstname=new string[size];
string* surname=new string[size];
string* address=new string[size];
cout<<"First Name"<<endl;
for (int i=0;i<size;i++)
    getline (cin, firstname[i]);
cout<<"Surname"<<endl;
cin.ignore();
for (int i=0;i<size;i++)
    getline (cin, surname[i]);
cout<<"Address"<<endl;
cin.ignore();
for (int i=0;i<size;i++)
    getline (cin, address[i]);
for (int i=0;i<size;i++)
{
    cout<<"First Name "<<firstname[i]<<endl;
    cout<<"Surname "<<surname[i]<<endl;
    cout<<"Age "<<address[i]<<endl;
}

EDIT: Sample Input/Output

Please enter the number of entries

4

First Name

John

Michael

Daniel

Radu

Surname

Laaksonen

Taro

Albot

Smith

Address

123 Larkin Street

900 Larkin Street

823 Larkin Street

283 Larkin Street

**First Name John

Surname aaksonen

Address 23 Larkin Street

First Name Michael

Surname Taro

Address 900 Larkin Street

First Name Daniel

Surname Albot

Address 823 Larkin Street

First Name Radu

Surname Smith

Address 283 Larkin Street**

Bold is the program's output. See how the L in Laaksonen is missing and the 1 in 123 is missing.

Upvotes: 0

Views: 25861

Answers (2)

Scott Hunter
Scott Hunter

Reputation: 49803

An alternative would be to read all using getline(), and parse the integer (using atoi or some such) yourself, avoiding the need for ignore entirely.

Upvotes: 0

Adriano Repetti
Adriano Repetti

Reputation: 67090

getline() reads and discard delimiter (reference), you have to use cin.ignore() only when you read your first integer:

cout<<"First Name"<<endl;
for (int i=0;i<size;i++)
    getline (cin, firstname[i]);

cout<<"Surname"<<endl;
// Remove this: cin.ignore();
for (int i=0;i<size;i++)
    getline (cin, surname[i]);

cout<<"Address"<<endl;
// Remove this: cin.ignore();
for (int i=0;i<size;i++)
    getline (cin, address[i]);

That said you may avoid standard arrays, a std::vector<std::string>> firstNames would be more appropriate.

Upvotes: 4

Related Questions