QString to char*

[A Former User]

@Dejavu Hi, and welcome to the Qt forum!

#include <QString>
#include <QList>
#include <QDebug>
#include <QPair>

typedef QPair<QChar, int> YourPair;
typedef QList<YourPair> YourList;

YourList computeYourHomework(const QString &s) {
    QList<QChar> list;
    for (int i=0; i<s.size(); i++) {
        const QChar c(s.at(i));
        if (!list.contains(c)) {
            list << c;
        }
    }
    YourList result;
    for (int i=0; i<list.size(); i++) {
        const QChar c(list.at(i));
        const int count = s.count(c);
        result << YourPair(c,count);
    }
    return result;
}

void printYourHomework( const YourList &list )
{
    for (int i=0; i<list.size(); i++) {
        const YourPair pair = list.at(i);
        qDebug() << QString("'%1' - %2").arg(pair.first).arg(pair.second);
    }
}

int main(int argc, char *argv[])
{
    Q_UNUSED(argc)
    Q_UNUSED(argv)
    const YourList result = computeYourHomework("bodya_krasavka_epta");
    printYourHomework(result);
    return 0;
}

Cheers!

[Dejavu]

Thank's a lot for help. How i can get a access to values in QList to edit characters or counter?

[jsulm]

See here http://doc.qt.io/qt-5/qlist.html

list[i] = ...

[Dejavu]

Thanks a lot to all and thank you so much @Wieland

[A Former User]

@Dejavu You're welcome ;-)

[Dejavu]

@Wieland sorry for new stupid question)
When I try to display the text in textEdit I got this error: C2227: left of '->textEdit' must point to class/struct/union/generic type

void printYourHomework( const YourList &list)
{
double *mynum, *freq, diap;
double *cum_freq;
double temp_cum = 0.0;
for (int i=0; i<list.size(); i++)
{
mynum = new double[i];
freq = new double[i];
cum_freq = new double[i];
}
for (int i=0; i<list.size(); i++) {
const YourPair pair = list.at(i);
MainWindow::ui->textEdit->append(QString("'%1' - %2").arg(pair.first).arg(pair.second));
mynum[i] = pair.second;
freq[i] = mynum[i]/18;
MainWindow::ui->textEdit->append(QString::number(freq[i], 'f', 8));
}

[mrjj]

@Dejavu said:

MainWindow::ui->textEdit->

That might be the reason.
You cannot access mainwindows UI outside of mainwindow.

So easy fix is to move the functions to mainwindow
( remember to add it to the mainwin.h file too)

YourList MainWindow::computeYourHomework(const QString &s) {
..
ui->textEdit->append(xxx
}

[Dejavu]

@mrjj thank you for the reply
I add it to mainwin file:

private slots:
YourList computeYourHomework(const QString &s);
void printYourHomework(const YourList &list);

and then i received errors:
http://prntscr.com/b2hmp6

I add function in mainwindow.cpp.

[mrjj]

@Dejavu
Hi
Maybe dont list it as slots. ( not the real error)
just put it under
private:

Then u also need to make sure it knows
YourList type
so u must move that over mainwindow class
or put in its on file and
#include "YourList .h"

[Dejavu]

@mrjj thank u so much.

I fix this problem. I just add #include in header and now it works.
Thanks a lot :)

[mrjj]

@Dejavu
Super :)