QStringLIst get duplicates ?

[sonichy]

First, I need to chop(1) every QString in QStringList.
Second, get duplicate 2, 3 ,4 times QString .

[aha_1980]

@sonichy

So like here: https://stackoverflow.com/questions/40999746/looking-inside-a-qstringlist-for-duplicate-strings-and-getting-a-count-of-duplic ?

[sonichy]

@aha_1980 Miraculous！

QMap<QString,int> countOfStrings;
QStringList listOfStrings;
listOfStrings << "a" << "b" << "c" << "a";
for(int i=0; i<listOfStrings.count(); i++)
{
    countOfStrings[listOfStrings[i]]++;
}
qDebug() << countOfStrings;

But how to read 2 times item out ?

[jsulm]

@sonichy said in QStringLIst get duplicates ?:

But how to read 2 times item out ?

What do you mean?

[J.Hilk]

Hi @sonichy I'm at a loss what you want to do in the first place, what does:

I need to chop(1) every QString in QStringList.

mean?

Do you have a QStringList and you want to reduce all QStrings in that list down to 1 character only?

    QStringList myStringList({"abc", "bca", "aaced", "fgh"});
    for( QString &str: myStringList)
        if(!str.isEmpty())
             str = str.at(0);
//will result in (a, b,a,f);

[JonB]

@J.Hilk , @sonichy
At the risk of guessing the OP's intentions, I have a feeling he actually means "how does he find (and remove, or not count?) any duplicates in the QStringList"? Hmm, maybe not quite, since he's already counting that in his QMap. Maybe he wants to output each string the number of times in the count for that string. Maybe I'm talking nonsense and it's to do with the "chop(1)". I love this guessing game.... :)

[J.Hilk]

@JonB
well QStringList is a complex tool and has for nearly everything a build in function:

There's removeDuplicates, to remove Duplicates ;-)
There's count(const T &), that returns how often the QString is in the list
and there's indexOf(const T &, int ) that returns the char index of the first appearence of the QString from the specified int-index on forward

[sonichy]

@J.Hilk Count(T) is easier and basic than QMap !

[JKSH]

@sonichy said in QStringLIst get duplicates ?:

@J.Hilk Count(T) is easier and basic than QMap !

Yes, it is easier.

It is also less efficient if you count many different strings.