#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    /**********ÀàÐÍת»»´íÎó**********/
    //1.ÒþʽÀàÐÍת»»µ¼Öµľ«¶ÈËðʧ
    double numDouble = 3.1415926;
    int numInt = numDouble; // Òþʽת»»£¬¾«¶ÈËðʧ£¬Ã»ÓнøÐÐÏÔʽ static_cast
    //int numInt = static_cast<int>(numDouble); // ÏÔʽת»»£¬Ã÷È·±íʾ½ÓÊܾ«¶ÈËðʧ
    //int numInt = (int)numDouble;

    //2.Ç¿ÖÆÀàÐÍת»»´íÎó
    void* void_ptr = nullptr;
    int* int_ptr = static_cast<int*>(void_ptr); // Ç¿ÖÆת»»´íÎó£¬void Ö¸Õë²»ÄÜÖ±½ÓתΪÓзûºÅÀàÐÍÖ¸Õë

    //3.ת»»ÀàÐͺó×îºÃÅжÏÒ»ÏÂÊÇ·ñת»»³É¹¦£¬Ö¸ÕëÊÇ·ñΪ¿Õ


    /**********Âß¼­´íÎó**********/
    // 1.Ñ­»·ÎÞÍ˳öÌõ¼þ£¨ËÀÑ­»·£©
    for (int i = 0; ; i++) {
        // Ñ­»·Ìå
    }
    //2.Êý×éÔ½½ç
    int array[10];
    array[10] = 0;// Ô½½ç·ÃÎÊÈÝÆ÷ÔªËØ
    std::vector<int> vec(5);
    vec[10] = 0; // Ô½½ç·ÃÎÊÈÝÆ÷ÔªËØ

    //3.Ìõ¼þÅжÏÖеÄÂß¼­ÔËËã·ûÎóÓã¨= ´úÌæ ==£©
    int a = 5, b = 10;
    if (a = b) { // ÎóÓà = ´úÌæ ==£¬´Ë´¦Âß¼­¶Ì·£¬a ±»¸³ÖµÎª b µÄÖµ£¬Ìõ¼þΪÕæ
        // Ö´ÐдúÂë¿é
    }

    //4.δ³õʼ»¯±äÁ¿µÄʹÓÃ
    int uninitialized;
    if (uninitialized > 0) { // ʹÓÃδ³õʼ»¯±äÁ¿£¬¿ÉÄܵ¼ÖÂ䶨ÒåÐÐΪ
        // Ö´ÐдúÂë¿é
    }

    /**********ÄÚ´æ¹ÜÀí´íÎó**********/
    //1.ÒýÓÿÕÖ¸Õë
    int* ptr = new int[5];
    delete[] ptr;
    ptr[0] = 10; // Ö¸ÕëÒÑÐü¿Õ£¬ÈÔ³¢ÊÔ·ÃÎÊ

    //2.ÄÚ´æй¶
    int* pt = new int[10];
    // ûÓÐ delete[] pt

    /**********ÆäËû´íÎó**********/
    //δʹÓõıäÁ¿
    int unused = 0;
}

MainWindow::~MainWindow()
{
    delete ui;
}