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Understanding recursion [closed]
...lly called "left" and "right"; again the children can be nodes, or null. A root is a node that is not the child of any other node.
Imagine that a node, in addition to its children, has a value, a number, and imagine that we wish to sum all the values in some tree.
To sum value in any one node, we ...
Why are the Level.FINE logging messages not showing?
...
The Why
java.util.logging has a root logger that defaults to Level.INFO, and a ConsoleHandler attached to it that also defaults to Level.INFO.
FINE is lower than INFO, so fine messages are not displayed by default.
Solution 1
Create a logger for your wh...
How to print binary tree diagram?
... private static Node<Integer> test1() {
Node<Integer> root = new Node<Integer>(2);
Node<Integer> n11 = new Node<Integer>(7);
Node<Integer> n12 = new Node<Integer>(5);
Node<Integer> n21 = new Node<Integer>(2);
...
How to select rows that have current day's timestamp?
... the `` are important because timestamp (and date as in my case) is a MySQL reserved word
– Victor Ferreira
Jan 10 '15 at 19:39
...
What is the difference between build.sbt and build.scala?
...cala:
import sbt._
import Keys._
object Build extends Build {
lazy val root = Project(id = "root", base = file(".")).settings(
name := "hello",
version := "1.0"
)
}
The .sbt file can also include vals, lazy vals, and defs (but not objects and classes).
See the SBT document cal...
SQL - find records from one table which don't exist in another
I've got the following two SQL tables (in MySQL):
8 Answers
8
...
How Do I Use Factory Girl To Generate A Paperclip Attachment?
...oryBot.define do
factory :user do
avatar { fixture_file_upload(Rails.root.join('spec', 'photos', 'test.png'), 'image/png') }
end
end
In the above example, spec/photos/test.png needs to exist in your application's root directory before running your tests.
Note, that FactoryBot is a new nam...
How to find where gem files are installed
...shims
- /Users/ttm/.rbenv/bin
- /Users/ttm/bin
- /usr/local/mysql-5.6.12-osx10.7-x86_64/bin
- /Users/ttm/libsmi/bin
- /usr/local/bin
- /usr/bin
- /bin
- /usr/sbin
- /sbin
- /usr/local/bin
Notice the two sections for:
INSTALLATION DIRECTORY
GEM PA...
No @XmlRootElement generated by JAXB
...nted at, the rules by which JAXB XJC decides whether or not to put the @XmlRootElement annotation on a generated class are non trivial (see this article).
@XmlRootElement exists because the JAXB runtime requires certain information in order to marshal/unmarshal a given object, specifically the XML ...
MongoDB - admin user not authorized
...ad around the same issue, and everything worked after I set the role to be root when adding the first admin user.
use admin
db.createUser(
{
user: 'admin',
pwd: 'password',
roles: [ { role: 'root', db: 'admin' } ]
}
);
exit;
If you have already created the admin user, you can chan...