用控制符控制输出格式

#include <iostream>
#include <iomanip>
/* run this program using the console pauser or add your own getch, system("pause") or input loop */
using namespace std;
int main(int argc, char** argv) {
    int a;
    cout<<"input a:";
    cin>>a;
    cout<<"dec:"<<dec<<a<<endl;
    cout<<"hex:"<<hex<<a<<endl;
    cout<<"oct:"<<setbase(8)<<a<<endl;
    char *pt="China";
    cout <<setw(10)<<pt<<endl;
    cout <<setfill('*')<<setw(10)<<pt<<endl;
    double pi=22/7;
    cout<<setiosflags(ios::scientific)<<setprecision(8);
    cout<<"pi="<<pi<<endl;
    cout<<"pi="<<setprecision(4)<<pi<<endl;
    cout<<"pi="<<setiosflags(ios::fixed)<<pi<<endl;
    return 0;
}