Visual C++ 2008入门经典 第三章判断和循环 简单

// 第三章判断和循环
/* 
3.1 比较数据值
    3.1.1 if语句
	//A-Z 是65-90
	//a-z 97-122
	//有一个将小写字母转换为大写的ISO/ANSI C++库函数 toupper()
	位于标准文件<ctype>中 

	3.1.3 扩展的if语句

	3.1.4 嵌套的if-else语句

	3.1.5 逻辑运算符和表达式
	&&  逻辑与
	||  逻辑或
	!   逻辑非

	3.1.6 条件运算符

	3.1.7 switch语句

	3.1.8 无条件转移

3.2 重复执行语句块
    3.2.1 循环的概念

	3.2.2 for循环的变体
	1. 使用continue
	2. 浮点循环计数器

	3.2.3 while循环

	3.2.4 do - while循环

	3.2.5 嵌套的循环

3.3 C++/CLI编程
	*/
//练习题一
//#include <iostream>
//using namespace std;
//int main()
//{
	//while循环
	/*int value=0, sum=0, i=0;
	bool tmp=true;
	while(tmp==true)
	{
	    cout<<"请输入你要计算的数值(值为0时结束):";
		cin>>value;
		if(value == 0){
		    tmp=false;
		}
	    sum +=value;
		i++;
	}
	cout<<"一共输入了"<<i<<"次,总数为:"<<sum<<endl;*/

	/*int value=0, sum=0, i=0;
	bool tmp=true;
	for(;;){
	    cout<<"请输入你要计算的数值(值为0时结束):";
		cin>>value;
		if(value == 0){
		    break;
		}
	    sum +=value;
		i++;
	}
	cout<<"一共输入了"<<i<<"次,总数为:"<<sum<<endl;*/
	
	/*int value=0, sum=0, i=0;
	bool tmp=true;
	do{
	    cout<<"请输入你要计算的数值(值为0时结束):";
		cin>>value;
		if(value == 0){
		    tmp=false;
		}else{
			sum +=value;
			i++;
		}
	}while(tmp==true);
	cout<<"一共输入了"<<i<<"次,总数为:"<<sum<<endl;


    return 0;*/
//}


//练习题二
/*#include <iostream>
using namespace std;
int main()
{
    char value=0;
	int number=0;
	for(;;)
	{
	     cout<<"请输入字符进行计算(输入q退出):";
		 cin>>value;
		 if(value=='q' || value == 'Q'){
		     break;
		 }
		 switch(value){
		 case 'a':
		 case 'e':
		 case 'i':
		 case 'o':
		 case 'u':
			 number += 1;
			 break;
		 }
	}
	cout<<"一共输入了"<<number<<"次元音字母"<<endl;
    return 0;
}*/


//练习题三
/*#include <iostream>
#include <iomanip>
using namespace std;
int main()
{
	//cout<<setw(17);
	for(int i=1; i<=12; i++){
		if(i==1)
			cout<<setw(8)<<" ";
	     cout<<setw(5)<<i;
	}

	cout<<endl;
	for(int i=2; i<=12; i++)
	{
		cout<<setw(5)<<i<<" | "<<setw(5);
		for(int j=1; j<=i; j++)
		{
		    cout<<setw(5)<<i*j;
		}
	    cout<<endl;
	}
    return 0;
}*/

//练习题四
#include <iostream>
using namespace std;
//十六进制数
const int text = 0x01;    //0000 0000 0000 0001 ===1
const int binary = 0x02;  //0000 0000 0000 0002 ===2
const int read = 0x10;    //0000 0000 0000 0010 ===16
const int write = 0x20;   //0000 0000 0000 0020 ===32
const int append = 0x40;  //0000 0000 0000 0040 ===64

int main()
{
	int mode=0;
	for(int modeSelect =0; modeSelect <6; modeSelect++)
	{
		cout<<"modeSelect:"<<modeSelect<<endl;
		switch(modeSelect)
		{
		case 0:
			mode = text | read;
			//0000 0000 0000 0001
			//0000 0000 0000 0010
			//0000 0000 0000 0011 ==17
			//cout<<"mode:"<<mode<<endl;
			break;
		case 1:
			mode = text | write;
			//0000 0000 0000 0001
			//0000 0000 0000 0020
			//0000 0000 0000 0021 == 33
			//cout<<"mode:"<<mode<<endl;
			break;
		case 2:
			mode = text | append;
			//0000 0000 0000 0001
			//0000 0000 0000 0040
			//0000 0000 0000 0041 ==65
			//cout<<"mode:"<<mode<<endl;
			break;
		case 3:
			mode = binary | read;
			//0000 0000 0000 0002
			//0000 0000 0000 0010
			//0000 0000 0000 0012 ==18
			//cout<<"mode:"<<mode<<endl;
			break;
		case 4:
			mode = binary | write;
			//0000 0000 0000 0002
			//0000 0000 0000 0020
			//0000 0000 0000 0022 ==34
			//cout<<"mode:"<<mode<<endl;
			break;
		case 5:
			mode = binary | append;
			//0000 0000 0000 0002
			//0000 0000 0000 0040
			//0000 0000 0000 0042 ==66
			//cout<<"mode:"<<mode<<endl;
            break;
		}

		//确定被设定的模式,并输出它
		//0000 0000 0000 0011
		//0000 0000 0000 0001
		//0000 0000 0000 0001 ok text


		//0000 0000 0000 0011
		//0000 0000 0000 0012
		//0000 0000 0000 0010 ok binary
		//=====这里又弄不错了样,不知道&咱算出来的,是这样吗?
		//弄不懂哦

		//如果将16进制转换为32位的二进制然后进行 与操作,好像出现的是正确的
		if(mode & text){
		     cout<<"mode is (text,";
		}else if(mode & binary){
		     cout<<"mode is (binary,";
		}
		cout<<endl;

		if(mode & read){
		    cout<<"read)";
		}else if(mode & write){
		    cout<<"write)";
		}else if(mode & append){
		    cout<<"append)";
		}
		cout<<endl;
	}
	return 0;
}

//练习题五 -> 
//第五题
/*#include "stdafx.h"
#include <iostream>
using namespace System;

int main(array<System::String ^> ^args)
{
    
	ConsoleKeyInfo keypress;
	do{
		keypress = Console::ReadKey(true);
		Console::Write(L"You Pressed ");
		if(safe_cast<int>(keypress.Modifiers) > 0)
		{
			Console::WriteLine(L" {0}, ", keypress.Modifiers);
		}
		Console::WriteLine(L"{0} which is the {0} character",keypress.Key, keypress.KeyChar);
	}while(keypress.Key != ConsoleKey::Escape);

	system("pause");
    return 0;
}*/

//第六题
#include "stdafx.h"
#include <iostream>
using namespace System;


int main(array<System::String ^> ^args)
{
    String^ str="Hello world Xlc Aeiou @@@";

	int count=0, noLetter=0, Bletter=0, Sletter=0;

	for each(wchar_t ch in str)
	{
		//Console::Write(L"{0}",ch);
		//Char::IsLetter(ch)
		if(Char::IsLetter(ch)){
			if(ch>='A' && ch<='Z'){
				Bletter++;
			}else if(ch>='a' && ch<='z'){
				Sletter++;
			}		
		}else{
		    noLetter++;
		}
		count++;
	}
	Console::WriteLine(L"字符串长度为:{0} 大写字母为:{1} 小写字母为:{2} 其它字符为:{3}",count,Bletter,Sletter,noLetter);
	//cout<<"字符串长度为:"<<count<<" "<<Bletter<<" "<<Sletter<<" "<<noLetter<<endl;
    system("pause");
    return 0;
}

  

原文地址:https://www.cnblogs.com/xiangxiaodong/p/2732767.html