trees of depth 4 so the whole thing is depth for it is at depth - so what's under here is due to the four bonds to leaf nodes under here we have 2 to the 4 minus 1 as 8 leaf nodes living here and so forth so every Congress there's any leave of the expanded tree since it's a pretty code let me know overlapped it's a clean tree so the total number of leaves will be in this case 2 to the 4 or in general 2 to the L + 4 n Ln the maximum length code that you're considering so the opposite equality here that the number of leaves