suppose we are given a number 'N' and we want to count all integers >=1 and <=N that are divisible by 'A' or 'B' or 'C' and 'D' or 'E' or 'F' then the code for this would be:

int ans=0;
for(int i=1;i<=N;i++)
  if((i%A==0 || i%B==0 || i%C==0) && (i%D==0 || i%E==0 || i%F==0))
      ans++;

cout<<ans;

the above code would run in O(N) time; but suppose 'N' is too big then is there any faster way to accomplish the above task?????