This algorithm will generate all prime numbers less than n.
void prime()
{
int i,n,j;
printf("enter any number");
scanf("%d",&n);/*scan the number */ i=2;
while(i<n)
{ j=2;
while(j<=i-1)
{
if(i%j==0)
break;
else
j++;
}
if(j==i)
printf("%d\n",i);
i++;
}
}