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#include "mainwindow.h"
#include <cmath>

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{

    widget=new QWidget;
    QVBoxLayout *vb=new QVBoxLayout;
    widget->setLayout(vb);
    widget->setStyleSheet("background-color::white");
    this->setCentralWidget(widget);
    this->setFixedSize(500,500);
    x = (- (3 * 3.14)) + 100;
    y = cos (x) + 100;

}

MainWindow::~MainWindow()
{

}


void MainWindow::paintEvent(QPaintEvent *event)
{
    QPainter *painter = new QPainter(this);
    QPen pen(QColor(Qt::darkGreen));

    painter->drawPixmap(this->width(), this->height(), QPixmap());
    pen.setWidth(2);
    painter->setRenderHint(QPainter::Antialiasing, true);
    painter->setPen(pen);
    painter->setBrush(Qt::darkGreen);

    while (x < 3 * 3.14 + 100){

        prevX = x;
        prevY = y;

        x = x + 1;
        y = cos(x);

        curX = x;
        curY = y;
        
        painter->drawLine(prevX, prevY, curX, curY);
    }
    this->update();
}