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

int main()
{
    double fi=2.5666, fk;
    int k=10;
    cout << k << endl;
    cout.width(10);
    cout << k  ;
    cout.width(10);
    cout << k << endl;
    cout << setw(10)<<k<<setw(10)<<fi<<  endl;
    cout << setprecision(10) << 1.0/3.0 << ":";
    cout << setprecision(5) << 1.0/3.0 << endl;
     return(0);
}

$ ./a.exe
10
        10        10
        10    2.5666
0.3333333333:0.33333