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Manipulator	Description	Example (for item "Amy")
setw(n)	Sets the number of characters for the next output item only (does not persist, in contrast to other manipulators). By default, the item will be right-aligned, and filled with spaces. From <iomanip>	For n=7: "Amy"
setfill(c)	Sets the fill to character c. From <iomanip>	For c='*': ""****Amy""	"
left	Changes to left alignment. From <ios>	"Amy "
right	Changes to right alignment. From <ios>	" Amy"

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

int main() {
   cout << "Dog age in human years (dogyears.com)" << endl << endl;
   
   // set num char for each column, set alignment
   cout << setw(10) << left  << "Dog age" << "|";
   cout << setw(12) << right << "Human age" << endl;
   cout << "------------------------------" << endl;
   cout << setw(10) << left  << "2 months" << "|";
   cout << setw(12) << right << "14 months" << endl;
   cout << setw(10) << left  << "6 months" << "|";
   cout << setw(12) << right << "5 years" << endl;
   
   // set fill character, num char for each column, set alignment
   cout << setfill('-');
   cout << setw(10) << left  << "8 months" << "|";
   cout << setw(12) << right << "9 years" << endl;
   cout << setw(10) << left  << "1 year" << "|";
   
   // change fill character, num char for each column, set alignment
   cout << setfill('.');
   cout << setw(12) << right << "15 years" << endl;

   // change fill character, num char for each column
   cout << setfill('*') << setw(30) << "" << endl;
   
   return 0;
}

Of particular interest is how the setw() and setfill() manipulators are used in the last few lines. Note how they are used to create a line of 30 asterisks, without having to type 30 asterisks. . Most manipulators are persistent, meaning they change the state of the stream for all subsequent output. The exception is setw(), which only affects the next output item, defined that way likely because programmers usually only want to set the width of the next item and not all subsequent items.

Manipulator	Description
endl	Inserts a newline character '\n' into the output buffer, and informs the system to flush the buffer.	From <iostream>
flush	Informs the system to flush the buffer. From <iostream>