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Is it safe to use -1 to set all bits to true?
... to do it exactly as you have shown, since it is the most straight forward one. Initialize to -1 which will work always, independent of the actual sign representation, while ~ will sometimes have surprising behavior because you will have to have the right operand type. Only then you will get the mos...
difference between primary key and unique key
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Primary Key:
There can only be one primary key in a table
In some DBMS it cannot be NULL - e.g. MySQL adds NOT NULL
Primary Key is a unique key identifier of the record
Unique Key:
Can be more than one unique key in one table
Unique key can have NULL v...
Display two files side by side
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You can use pr to do this, using the -m flag to merge the files, one per column, and -t to omit headers, eg.
pr -m -t one.txt two.txt
outputs:
apple The quick brown fox..
pear foo
longer line than the last two bar
last ...
How to convert number to words in java
...or example
1000
1 is treated as thousand position and 1 gets mapped to "one" and thousand because of position
This is the code from the website:
English
import java.text.DecimalFormat;
public class EnglishNumberToWords {
private static final String[] tensNames = {
"",
" ten",
...
Is there ever a time where using a database 1:1 relationship makes sense?
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A 1:1 relationship typically indicates that you have partitioned a larger entity for some reason. Often it is because of performance reasons in the physical schema, but it can happen in the logic side as well if a large chunk of the data is expected to be "unknown" at the same time (i...
Is floating point math broken?
...I think you should add something to this answer about how computations on money should always, always be done with fixed-point arithmetic on integers, because money is quantized. (It may make sense to do internal accounting computations in tiny fractions of a cent, or whatever your smallest currenc...
Can a java file have more than one class?
What is the purpose of having more than one class in a Java file ? I am new to Java.
18 Answers
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What does 'low in coupling and high in cohesion' mean
...is about making sure module doesn't do many things, it is meant to do only one particular thing".
– Lokesh
May 2 '17 at 9:49
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Difference between numpy.array shape (R, 1) and (R,)
...For example, given a matrix M , if we want to do numpy.dot(M[:,0], numpy.ones((1, R))) where R is the number of rows (of course, the same issue also occurs column-wise). We will get matrices are not aligned error since M[:,0] is in shape (R,) but numpy.ones((1, R)) is in shape (1, R) ....
What is “the inverse side of the association” in a bidirectional JPA OneToMany/ManyToOne association
In the example section of the @OneToMany JPA annotation reference :
6 Answers
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