6.
int six(int n)
{
int i;
for (i=0;i<n;++i) printf("*");
/* no return value(minor bug) as in pascal code*/
}
int seven(int a,int b)
{
int i;
for (i=a;i<=b;++i)
printf("%d",i);
/*same bug*/
}
int eight(int n)
{
int i;
for (i=1;i<=n/2;++i)
if (n/i==0) printf ("0");
else printf("1");
/*same mistake, not return value*/
}