example program with c++

#define N 100 //creates a variable N with constant value 100
#define A 2 //creates a variable A with constant value 2

main() //start of the program
{
int a; //variable a declaration
a = A; //assigns value 2 to a

while (a < N) //while value of a is less than N
{ //evaluate or do the following
printf(“%d \n”,a); //print the current value of a
a *= a; //shorthand form of a = a * a
} //end of the loop
} //end of the program