Program understand textcolor() and textbackground() function

using turboc++
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//understanding textcolor in graphics
#include<stdio.h>
#include<conio.h>// contains textcolor() and text background().
void main()
{
clrscr();
textbackground(RED);  //Sets background red
textcolor(GREEN);    //sets textcolor green
cprintf("first line...........\n");
textcolor(GREEN);
textbackground(BLUE);
cprintf("This is a test\n");//sends formatted output to the text window on the screen
  //Does not work with printf.
getch();
}

/*second part prints line from that location where
first part is finished
*/
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