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Fastest way to check if a file exist using standard C++/C++11/C?

...e thousands of files and before doing something on them I need to check if all of them exist. What can I write instead of /* SOMETHING */ in the following function? ...
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mysql - how many columns is too many?

...eral rule, your table structure should reflect your domain model; if you really do have 70 (100, what have you) attributes that belong to the same entity there's no reason to separate them into multiple tables. share ...
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Are there disadvantages to using a generic varchar(255) for all text-based fields?

...stcode , first name , last name , town , country , phone number etc, all of which are defined as VARCHAR(255) even though none of these fields will ever come close to having 255 characters. (If you're wondering, it's this way because Ruby on Rails migrations map String fields to VARCHAR(25...
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How many characters can UTF-8 encode?

... UTF-8 does not use one byte all the time, it's 1 to 4 bytes. The first 128 characters (US-ASCII) need one byte. The next 1,920 characters need two bytes to encode. This covers the remainder of almost all Latin alphabets, and also Greek, Cyrilli...
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Global variables in Java

... public static int b; } now you can access a and b from anywhere by calling Example.a; Example.b; share | improve this answer | follow | ...
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Responsive image map

...ponsive image maps you will need to use a plugin: https://github.com/stowball/jQuery-rwdImageMaps (No longer maintained) Or https://github.com/davidjbradshaw/imagemap-resizer No major browsers understand percentage coordinates correctly, and all interpret percentage coordinates as pixel c...
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Delete commits from a branch in Git

... IN PROGRESS. It will reset you back to the most recent commit, and erase all the changes in your working tree and index. Lastly, if you need to find a commit that you "deleted", it is typically present in git reflog unless you have garbage collected your repository. ...
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Random number from a range in a Bash Script

... Also, it's probably fine for this use, but I believe shuf does actually permute the entire input. This makes it a bad choice if you're generating the random numbers very frequently. – Cascabel Mar 31 '10 at 20:42 ...
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Get type of all variables

...(c(TRUE, FALSE)) #a vector containing only logicals: logical #R is really cramping my style, killing my high, irritation is increasing: typeof(factor()) #an empty factor has default type: integer typeof(factor(3.14)) #a factor containing doubles: integer typeof(factor(...
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How to select option in drop down protractorjs e2e tests

... I had a similar problem, and eventually wrote a helper function that selects dropdown values. I eventually decided that I was fine selecting by option number, and therefore wrote a method that takes an element and the optionNumber, and selects that optionNumb...