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Difference between signed / unsigned char [duplicate]
So I know that the difference between a signed int and unsigned int is that a bit is used to signify if the number if positive or negative, but how does this apply to a char ? How can a character be positive or negative?
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Why does C++ rand() seem to generate only numbers of the same order of magnitude?
In a small application written in C/C++, I am facing a problem with the rand function and maybe the seed :
9 Answers
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How to check whether a pandas DataFrame is empty?
How to check whether a pandas DataFrame is empty? In my case I want to print some message in terminal if the DataFrame is empty.
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How do I create and read a value from cookie?
How can I create and read a value from a cookie in JavaScript?
19 Answers
19
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Declaration/definition of variables locations in ObjectiveC?
Ever since starting to work on iOS apps and objective C I've been really puzzled by the different locations where one could be declaring and defining variables. On one hand we have the traditional C approach, on the other we have the new ObjectiveC directives that add OO on top of that. Could you fo...
Understanding the map function
Apply function to every item of iterable and return a list of the results. If additional iterable arguments are passed, function must take that many arguments and is applied to the items from all iterables in parallel.
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Check if at least two out of three booleans are true
...ewer recently asked me this question: given three boolean variables, a, b, and c, return true if at least two out of the three are true.
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Convert int to char in java
...onding to '1')
If you want to convert a digit (0-9), you can add 48 to it and cast, or something like Character.forDigit(a, 10);.
If you want to convert an int as in ascii value, you can use Character.toChars(48) for example.
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Catching error codes in a shell pipe
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If you really don't want the second command to proceed until the first is known to be successful, then you probably need to use temporary files. The simple version of that is:
tmp=${TMPDIR:-/tmp}/mine.$$
if ./a > $tmp.1
then
if ./b <$tmp.1 >$tmp.2
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What is the significance of load factor in HashMap?
HashMap has two important properties: size and load factor . I went through the Java documentation and it says 0.75f is the initial load factor. But I can't find the actual use of it.
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