Question

阅读下列程序，写出运行结果。(c++基础)

#include<iostream>
using namespace std;
int main()
{
doublex = 123.45678;
cout.width( 10 );
cout<<("#" );
cout<<x<<endl;
cout.precision( 5 );
cout<<x<<endl;
cout.setf(ios::showpos );
cout<<x<<endl;
cout.setf(ios::scientific );
cout<<x<<endl;
}
#include<iostream>
using namespace std;
int main()
{
doublex = 123.45678;
cout.width( 10 );
cout<<("#" );
cout<<x<<endl;
cout.precision( 5 );
cout<<x<<endl;
cout.setf(ios::showpos );
cout<<x<<endl;
cout.setf(ios::scientific );
cout<<x<<endl;
}
标志字到底是怎么弄的~我看不懂~求搭救

Answer 1

#123.457宽度10然后打印#，打印x
123.46//以精度5打印x
+123.46//显示符号
+1.23457e+002//科学计数形势

Answer 2

#123.457
123.46
+123.46
+1.23457e+002