/*  Rewritign Code (part a) */ 

#include <stdio.h>
#include <stdlib.h>

int main(void)
{
	// Original
/*	
	int n;
	do 
	{
   		printf("Enter a number: ");
		scanf("%d", &n);
	} while(n<0);
*/
	// Rewritten
	int n=-1;
	for(;n<0;)
	{
   		printf("Enter a number: ");
		scanf("%d", &n);
	}
	
    system("pause");
}