请指教啊！width

/*如果输入abcdefgh，希望输出abcd efgh，width的填写*/

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

int main()
{
char buffer1[10],buffer2[10];
cout<<"请输入abcdefgh"<<endl;
cin.width(5);
cin>>buffer1>>buffer2;
cout.width(4);
cout<<buffer1<<" "<<buffer2<<endl;
return 0;

为啥啊
cin.width(5);
cout.width(4);