C++ program to shutdown windows7 :

#include <stdio.h>
#include <stdlib.h>
main ()
{
char ch ;
printf ("Do you want to shutdown your computer now (y/n) \n ") ;
scanf ( "%c" ,& ch ) ;
if ( ch == 'y' || ch == 'Y' )
system ( "C: \\ WINDOWS\\ System32 \\ shutdown /s" ) ;
return 0 ;
}

Happy Coding..