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Odd behavior when Java converts int to byte?

...+ unsignedByte); Would print out: "Signed: -1 Unsigned: 255" What's actually happening here? We are using bitwise AND to mask all of the extraneous sign bits (the 1's to the left of the least significant 8 bits.) When an int is converted into a byte, Java chops-off the left-most 24 bits 111111...
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How to prove that a problem is NP complete?

... As far as I remember, there is a theorem called the Cook-Levin theorem which states that SAT is NP-complete. That proof is quite a bit more complicated than what I outlined above and I don't think I can explain it in my own words. – Laila Agaev ...
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Timing a command's execution in PowerShell

...turn the average, minimum and maximum time taken. You can add -Silent to swallow STDOUT. – joshuapoehls Mar 26 '12 at 18:11 13 ...
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Structure padding and packing

.... A note though - unaligned memory access is slower on architectures that allow it (like x86 and amd64), and is explicitly prohibited on strict alignment architectures like SPARC. share | improve t...
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How can I use “:” as an AWK field separator?

... If you want to do it programatically, you can use the FS variable: echo "1: " | awk 'BEGIN { FS=":" } /1/ { print $1 }' Note that if you change it in the main loop rather than the BEGIN loop, it takes affect for the next line read in, since the current l...
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Exposing database IDs - security risk?

... extremely burdensome to design a web application without exposing them at all. Thus, it's important to understand the risks and take care to address them. The first danger is what OWASP called "insecure direct object references." If someone discovers the id of an entity, and your application lacks ...
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String concatenation in Ruby

...ficient in term of memory/speed from what I've seen (not measured though). All three methods will throw an uninitialized constant error when ROOT_DIR is nil. When dealing with pathnames, you may want to use File.join to avoid messing up with pathname separator. In the end, it is a matter of taste....
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How do I add custom field to Python log format string?

...LoggerAdapter so you don't have to pass the extra info with every logging call: import logging extra = {'app_name':'Super App'} logger = logging.getLogger(__name__) syslog = logging.StreamHandler() formatter = logging.Formatter('%(asctime)s %(app_name)s : %(message)s') syslog.setFormatter(formatte...
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How do I make XAML DataGridColumns fill the entire DataGrid?

...Width="*" the column will fill to expand the available space. If you want all columns to divide the grid equally apply this to all columns. If you just want one to fill the remaining space just apply it to that column with the rest being "Auto" or a specific width. You can also use Width="0.25*" (...
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Email address validation using ASP.NET MVC data type attributes

... Validating email addresses with regex is usually a terrible idea... but if you must, there's an excellent reference here.. regular-expressions.info/email.html – Molomby Jul 23 '14 at 4:18 ...