c++ 程序意想不到的简洁清晰

[baigoo]

//============================================================================
// Name        : std1.cpp
// Author      : chenyan
// Version     :
// Copyright   : Your copyright notice
// Description : Hello World in C++, Ansi-style
//============================================================================

#include <iostream>
#include <iomanip>
#include <locale>
using namespace std;

class A{
public:
	A(){total++;cout << "调用无参构造函数" << endl;};
	A(int num):it(num){total++;cout << "调用有参构造函数" << endl;}
	~A(){total--;}
	static int total;
	void set(int num){it = num;}
	int get(){return it;}
private:
	int it;
};
int A::total = 0;

int main() {
	A mya;
	char ch = 'a';
	const double PI = 3.1415926;
	int a  = 0X10;
	mya.set(100);
	cout << "mya.tatal="<< mya.total << endl;
    cout <<"mya.it="<< mya.get() << endl;
    cout << "OCT:"<< oct << "a=0"<< a << endl; //以八进制显示
    cout << "DEC:"<< dec << "a="<< a << endl; //以十进制显示
    cout << "HEX:"<< hex << "a=0X"<< a << endl; //以十六进制显示
    cout << "ASCII:'"<< ch << "'=" << (int)ch << endl;//字符a的ASCII码
    cout << dec;//下面全部内容以十进制格式显示
    cout <<"bool "<<"false:"<<false <<" true:"<< true << endl;
    cout << "char:"<<sizeof(char)<<endl;
    cout << "wchar_t:"<<sizeof(wchar_t)<<endl;
    cout << "short:"<<sizeof(short)<<endl;
    cout << "unsigned int:"<<sizeof(unsigned int)<<endl;
    cout << "signed int:"<<sizeof(signed int)<<endl;
    cout << "long int:"<<sizeof(long int)<<endl;
    cout << "long long:"<<sizeof(long long)<<endl;
    cout << "float:"<<sizeof(float)<<endl;
    cout << "double:"<<sizeof(double)<<endl;
    cout << "long double:"<<sizeof(long double)<<endl;//ANSI C99标准
    cout << "double long:"<<sizeof(double long)<<endl;
    cout << "PI="<< setprecision(8) << PI << endl;//设置输出的有效位为8位，cout默认最长
                                                  //输出精度为6位
    for(int i = 1;i <= 9;i ++){
    	for(int j = 1;j <= i;j ++){
    		cout << j << "*" << i << "=" << i * j;
    		cout << "\t";
    	}
    	cout << endl;
    }

	return 0;
}

执行结果：

[vipcxj]

我来接分

[阿桑-]

收获了！！！！

[阿桑-]

菜鸟问一下？ cout<<"OCT : \t"<<oct<<"a = "<<a<<endl; 输出后，是不是后面的变量值都是以八进制的输出？？期待大神？

[ztenv]

不错，不错，继续努力

[ztenv]

引用 3 楼 u010551600 的回复:

菜鸟问一下？ cout<<"OCT : \t"<<oct<<"a = "<<a<<endl; 输出后，是不是后面的变量值都是以八进制的输出？？期待大神？

除非你显示的设置为hex或dec，否则一直都是以oct格式输出（注意一直的意思）

[baigoo]

引用 6 楼 derekrose 的回复:

楼主对简洁的定义是？

比起c语言来说更加灵活自由？

[derekrose]

楼主对简洁的定义是？