5 replies to this topic

[Fang]

It's challenge time! This week's task is a fun one.


For a specified integer x , find the number of positive integers with binary representations, between 2 and 8 digits, that occur in the binary representation of x.

e.g. 11₁₀ =  1011₂
The combinations that occur are as follows: 1011, 101, 10, 11. So for the number 15, you should find 4 integers.

22₁₀ = 10110₂
The combinations that occur are as follows: 10110,1011,101,10,11,110. So for the number 22, you should find 6 integers.

560₁₀ = 1000110000₂
The combinations that occur are as follows:  10001100, 1000110, 100011, 10001, 1000, 100, 10, 11, 110000, 11000, 1100, 10000, 110. So for the number 560, you should find 13 integers.


Remember, 2 to 8 digits. So 1 and 0 don't count, and neither do integers of more than 8 bits. x can take a value up to 65536.

Entries posted here: http://0x10command.c...allenge/week-5/

[Erocs]

Fang, on 11 June 2012 - 10:37 PM, said:

For a specified integer x , find the number of positive integers with binary representations, between 2 and 8 digits, that occur in the binary representation of x.

560₁₀ = 1000110000₂
The combinations that occur are as follows: 1000110000, 100011000, 10001100, 1000110, 100011, 10001, 1000, 100, 10, 11, 110000, 11000, 1100, 110. So for the number 560, you should find 14 integers.

Remember, 2 to 8 digits. So 1 and 0 don't count, and neither do integers of more than 8 bits. x can take a value up to 65536.

Did you mean to include 1000110000 and 100011000? They contain more than 8 binary digits.  

[Fang]

Erocs, on 12 June 2012 - 09:41 PM, said:

Did you mean to include 1000110000 and 100011000? They contain more than 8 binary digits.  

Good catch. Nope, I didn't mean to include them. I've fixed the above.

[Erocs]

Just a couple more things. 1011₂ == 11₁₀ not 15₁₀. For 560₁₀, you missed the 10000 pattern so there are 13 values.

Also, I was playing around and submitted my answer as private. Now I can't find a way to make it public again, lol.

[Fang]

Well that's embarrassing. I've fixed them again, thanks!

If on the code page, you click "Edit" it will take you to the edit page. Here click "Save Edit" and in the dropdown panel uncheck the box which says Draft/Private?

[Erocs]

Ahh thanks, I was thinking that it would be on the Settings page so I never clicked save to once again see the submit settings page.