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How to find the kth largest element in an unsorted array of length n in O(n)?
...A2.
Let's guess that T(n) <= an for some a. Then we get
T(n)
<= cn + (1/n) ∑i=1 to nT(max(i-1, n-i))
= cn + (1/n) ∑i=1 to floor(n/2) T(n-i) + (1/n) ∑i=floor(n/2)+1 to n T(i)
<= cn + 2 (1/n) ∑i=floor(n/2) to n T(i)
<= cn + 2 (1/n) ∑i=floor(n/2) to n ai
and now somehow w...
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How to create a self-signed certificate with OpenSSL
...ry Name", but you can just hit Enter and accept the defaults.
Add -subj '/CN=localhost' to suppress questions about the contents of the certificate (replace localhost with your desired domain).
Self-signed certificates are not validated with any third party unless you import them to the browsers p...
Calculating moving average
...comment from @Ricardo Cruz:
cx <- c(0, cumsum(ifelse(is.na(x), 0, x)))
cn <- c(0, cumsum(ifelse(is.na(x), 0, 1)))
rx <- cx[(n+1):length(cx)] - cx[1:(length(cx) - n)]
rn <- cn[(n+1):length(cx)] - cn[1:(length(cx) - n)]
rsum <- rx / rn
This still has the issue that if all the values ...
Similar to jQuery .closest() but traversing descendants?
Is there a function similar to jQuery .closest() but for traversing descendants and returning only closest ones?
16 Ans...
Break a previous commit into multiple commits
...was farther back in the tree than you want to count, then
$ git rebase -i 123abcd~
where 123abcd is the SHA1 of the commit you want to split up.
If you are on a different branch (e.g., a feature branch) that you plan to merge into master:
$ git rebase -i master
When you get the rebase edit sc...
keytool error :java.io.IoException:Incorrect AVA format
...PatrickTaylor -validity 10000
-keystore C:\drops\patrickkeystore
-dname "cn=Patrick Taylor, ou=engineering, o=company, c=US"
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Strangest language feature
...
Fun with auto boxing and the integer cache in Java:
Integer foo = 1000;
Integer bar = 1000;
foo <= bar; // true
foo >= bar; // true
foo == bar; // false
//However, if the values of foo and bar are between 127 and -12...
CSS to stop text wrapping under image
... to use a <p> element as a parent for your <span>.
<li id="CN2787">
<img class="fav_star" src="images/fav.png">
<p>
<span>Text, text and more text</span>
</p>
</li>
Since <p> is a block element, you can set its width using CSS...
How do I find out which keystore was used to sign an app?
...oid.youtube-10.39.54-107954130-minAPI15.apk
Signer #1:
Signature:
Owner: CN=Unknown, OU="Google, Inc", O="Google, Inc", L=Mountain View, ST=CA, C=US
Issuer: CN=Unknown, OU="Google, Inc", O="Google, Inc", L=Mountain View, ST=CA, C=US
Serial number: 4934987e
Valid from: Mon Dec 01 18:07:58 PST 2008 ...