新建 文本文档.txt

资深C++讲师授课代码

cpp01
//hello.cc
/*
line 1
line 2
line 3
*/
#include <iostream>//预处理命令
using namespace/*名字空间*/ std;

int main()//main 函数
{
        cout << "Hello, world!" << endl;//console output
        cout << "This is my first C++ program.\n";
        cout << "welcome " << "to " << "tarena!" << endl;
        cout << "It is August " << 8 << "." << endl;
}


cpp02
//cmdline.cc
#include <iostream>
using namespace std;

int main(int argc, char* argv[])
{
        cout << "你好!" << endl;
        cout << "argc=" << argc << endl;
        cout << "您在命令行上有" << argc << "个字符串" << endl;
        return 0;
}
//hello.cc
#include <iostream>
using namespace std;

int main()
{
        cout << "你好!" << endl;
        return 0;
}
//input.cc
#include <iostream>
using namespace std;

int main()
{
        int age;
        cout << "age=" << age << endl;
        cout << "please input your age:";
        cin >> age;
        cout << "you are born in " << 2008-age << endl;
}
//size.cc
#include <iostream>
#include <cstring>
using namespace std;

int main(int argc, char* argv[])
{
        if(argc!=2)
        {
                cout << "只能带一个选项" << endl;
                cout << argv[0] << " -s|m|l|xl" << endl;
        }
        else
        {
                if(strcmp(argv[1], "-s")==0)
                {
                        cout << "您选择的是小号" << endl;
                }
                else if(strcmp(argv[1], "-m")==0)
                {
                        cout << "您选择的是中号" << endl;
                }
                else if(strcmp(argv[1], "-l")==0)
                {
                        cout << "您选择的是大号" << endl;
                }
                else if(strcmp(argv[1], "-xl")==0)
                {
                        cout << "您选择的是超大号" << endl;
                }
                else
                {
                        cout << "无效的选项!" << endl;
                        cout << argv[0] << " -s|m|l|xl" << endl;
                }
        }
}

bash-2.05$ cat time.cc
#include <iostream>
using namespace std;
#include <ctime>

int main()
{
        unsigned int now = time(NULL);
        cout << "now=" << now << endl;
        unsigned int second = now%60;
        unsigned int minute = now/60;
        minute = minute%60;
        unsigned int hour = now/3600+8;
        hour = hour%24;
        cout << hour << ':' << minute << ':' << second << endl;
}

bash-2.05$ cat argv.cc
#include <iostream>
using namespace std;

int main(int argc, char* argv[])
{
        cout << "你好!" << endl;
        cout << "argc=" << argc << endl;
        cout << "您在命令行上有" << argc << "个字符串" << endl;
        cout << "argv[0]=" << argv[0] << endl;
        cout << "argv[1]=" << argv[1] << endl;
        cout << "argv[2]=" << argv[2] << endl;
        cout << "argv[3]=" << argv[3] << endl;
        cout << "argv[4]=" << argv[4] << endl;
        cout << "argv[5]=" << argv[5] << endl;
        cout << "argv[6]=" << argv[6] << endl;
        return 0;
}

bash-2.05$ cat for.cc
#include <iostream>
using namespace std;

int main(int argc, char* argv[])
{
        cout << "你好!" << endl;
        cout << "argc=" << argc << endl;
        cout << "您在命令行上有" << argc << "个字符串" << endl;
        for(int i=0; i<argc; i++)
        {
                cout << "argv[" << i << "]=" << argv[i] << endl;
        }
        return 0;
}

bash-2.05$ cat hi.cc
#include <iostream>
#include <cstring>
using namespace std;

int main(int argc, char* argv[])
{
        if(argc==1)
        {
                cout << "你好!" << endl;
        }
        else
        {
                if(argc!=2)
                {
                        cout << "hi -m" << endl;
                        cout << "hi -a" << endl;
                        cout << "hi -e" << endl;
                }
                else
                {
                        if(strcmp(argv[1],"-m")==0)
                        {
                                cout << "早上好" << endl;
                        }
                        if(strcmp(argv[1],"-a")==0)
                        {
                                cout << "下午好" << endl;
                        }
                        if(strcmp(argv[1],"-e")==0)
                        {
                                cout << "晚上好" << endl;
                        }
                }
        }
        return 0;
}


bash-2.05$ cat int.cc
#include <iostream>
using namespace std;

int main(int argc, char* argv[])
{
        int age=20;
        cout << "age=" << age << endl;
        int nianling;
        cout << "nianling=" << nianling << endl;
        int nianling1;
        cout << "nianling1=" << nianling1<< endl;
        int nianling2;
        cout << "nianling2=" << nianling2<< endl;
        int nianling3;
        cout << "nianling3=" << nianling3<< endl;
        int nianling4;
        cout << "nianling4=" << nianling4<< endl;
        nianling4 = 30;
        cout << "nianling4=" << nianling4<< endl;
}

bash-2.05$ cat star.cc
#include <iostream>
using namespace std;
#include <cstdlib>

int main(int argc, char* argv[])
{
        if(argc != 2)
                cout << argv[0] << " number" << endl;
        else
        {
                for(int i=0; i<atoi(argv[1]); i++)
                {
                        cout << "*";
                }
                cout << endl;
        }
}

bash-2.05$ cat unsigned.cc
#include <iostream>
using namespace std;

int main()
{
        int integer;
        unsigned int ui;
        integer = -1;
        ui = -1;
        cout << "integer=" << integer << endl;
        cout << "ui=" << ui << endl;
}

cpp03
bash-2.05$ cat const.cc
#include <iostream>
using namespace std;

int main()
{
        int n;
        int m=10;
        //const int c=30;
        int const c=30;
        n = 40;
        m = n * 20;
        //c = 50;//ERROR!!
}

bash-2.05$ cat bits.cc
#include <iostream>
using namespace std;

int main()
{
        int n;
        cout << "请输入一个整数:";
        cin >> n;
        unsigned int m=0x80000000;//1000 0000 0000 0000 0000 0000 0...
        int counter = 0;
        for(int i=0; i<32; i++)
        {
                if((m&n)!=0)
                {
                        ++counter;
                        cout << 1;
                }
                else { cout << 0; }
                m >>= 1;
                if(i%4==3) { cout << ' '; }
        }
        cout << endl << counter << " 1s" << endl;
}

bash-2.05$ cat operator1.cc
#include <iostream>
using namespace std;

int main()
{
        cout << true << ',' << false << endl;
        cout << boolalpha << true << ',' << false << endl;
        cout << true << ',' << false << endl;
        cout << !true << ',' << !false << endl;
        int n=/*1000 1011 0101 1100 1010 0001 0110 1001*/0x8B5CA169;
        cout << hex << ~n << endl;
        cout << "n=" << n << endl;
}

bash-2.05$ cat operator2.cc
#include <iostream>
using namespace std;

int main()
{
        int a=10;
        int b=10;
        ++a;
        cout << a << endl;
        cout << ++b << endl;
        int c=10;
        int d=10;
        c++;
        cout << c << endl;
        cout << d++ << endl;
}

bash-2.05$ cat operator3.cc
#include <iostream>
using namespace std;

int main()
{
        double d=1.5;
        *&d = 4.8;
        cout << d << endl;
        cout << (int)d << endl;
        cout << d << endl;
        char c='A';
        cout << int(c) << endl;
        cout << (int)c << endl;
        int n=48;
        cout << (char)n << endl;
}

bash-2.05$ cat operator4.cc
#include <iostream>
using namespace std;

int main()
{
        int n=/*1000 1011 0101 1100 1010 0001 0110 1001*/0x8b5ca169;
        unsigned int m = 0x8b5ca169;
        cout << hex << (n<<4) << ',' << (m<<4) << endl;
        cout << "n=" << n << ", m=" << m << endl;
        cout << hex << (n>>4) << ',' << (m>>4) << endl;
}

bash-2.05$ cat switch.cc
#include <iostream>
using namespace std;

int main()
{
        int n;
        cout << "input 1~4:";
        cin >> n;
        switch(n){
                case 1:
                        cout << "1--存款" << endl;
                        break;
                case 2:
                        cout << "2--取款" << endl;
                        break;
                case 3:
                        cout << "3--查询" << endl;
                        break;
                case 4:
                        cout << "4--转账" << endl;
                        break;
                default:
                        cout << "无效选择" << endl;
        }
        cout << "谢谢!" << endl;
}


bash-2.05$ cat uncertain.cc
#include <iostream>
using namespace std;

int main()
{
        int i=4;
        int j=i--*i--*i--;
        cout << "j=" << j << endl;
        int a=4;
        cout << ++a << ++a << ++a << endl;
        int b=4;
        cout << b-- << b-- << b-- << endl;
}


bash-2.05$ cat union.cc
#include <iostream>
using namespace std;

int main()
{
        union{
                int a;
                int b;
        };
        a = 10;
        cout << "b=" << b << endl;
        b = 20;
        cout << "a=" << a << endl;
}

cpp04

bash-2.05$ cat float.cc
#include <iostream>
using namespace std;

int main()
{
        float f=0.0;
        for(int i=0; i<100; i++)
                f += 0.01;
        cout << "f=" << f << endl;
        float dif=1.0-f;
        if(dif<0.00001&&dif>-0.00001)
                cout << "equal to 1.0" << endl;
        if(f==1.0)
                cout << "==" << endl;
        else
                cout << "!=" << endl;
}

bash-2.05$ cat namespace.cc
#include <iostream>
using namespace std;
#include <ctime>

namespace czq{
        int v=20;
        int m=40;
}
using namespace czq;
namespace zdm{
        int v=30;
        int x=50;
}
using zdm::x;
int v=10;
int main()
{
        double v=9.9;
        long n = time(NULL);
        cout << "n=" << n << endl;
        if((n&1)==0)
        {
                const char* v="even";
                cout << v << endl;
                cout << ::v << endl;
        }
        cout << v << endl;
        cout << ::v << endl;
        cout << czq::v << endl;
        cout << zdm::v << endl;
        cout << m << endl;
        cout << x << endl;
        return 1234567;
}



bash-2.05$ cat static.cc
#include <iostream>
using namespace std;

int counter()
{
        static int cnt=0;
        return ++cnt;
}
int main()
{
        cout << counter() << endl;
        cout << counter() << endl;
        cout << counter() << endl;
        //cout << cnt << endl;//ERROR!!
}

bash-2.05$ cat triangle.cc
#include <iostream>
using namespace std;

void printline(int height, int line)
{
        for(int j=1;j<=line;j++)
        cout << (j==1||j==line||line==height?" *":"  ");
        cout << endl;
}
void printspace(int count)
{
        for(int i=0; i<count; i++)
                cout << ' ';
}
int main()
{
        int n;
        cout << "input height: ";
        cin >> n;
        for(int i=1; i<=n; i++)
        {
                printspace(n-i);
                printline(n, i);
        }
}

bash-2.05$ cat declare.cc
#include <iostream>
using namespace std;

int Max(int, int, int);
int main()
{
        cout << Max(3,9,2) << endl;
}

int Max(int a, int b, int c)
{
        int m=a>b?a:b;
        return m>c?m:c;
}

bash-2.05$ cat max.h
#ifndef max_h

#define max_h 1
int Max(int, int, int);
double pi=3.14;

#endif

bash-2.05$ cat parameter.cc
#include <iostream>
using namespace std;

void printstar(int count)
{
        for(int j=0;j<count;j++)
        cout << " *";
        cout << endl;
}
void printspace(int count)
{
        for(int i=0; i<count; i++)
                cout << ' ';
}
int main()
{
        printstar(5);
        printstar(13);
        printstar(6);
        for(int i=0; i<8; i++)
        {