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Why does this code using random strings print “hello world”?

...e share your code. I would greatly appreciate it. public static void main(String[] args) { long time = System.currentTimeMillis(); generate("stack"); generate("over"); generate("flow"); generate("rulez"); System.out.println("Took " + (System.currentTimeMillis() - time) + " ...
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How to create a memory leak in Java?

...eClass { static final ArrayList list = new ArrayList(100); } Calling String.intern() on lengthy String String str=readString(); // read lengthy string any source db,textbox/jsp etc.. // This will place the string in memory pool from which you can't remove str.intern(); (Unclosed) open strea...
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What is the C# equivalent of NaN or IsNumeric?

What is the most efficient way of testing an input string whether it contains a numeric value (or conversely Not A Number)? I guess I can use Double.Parse or a regex (see below) but I was wondering if there is some built in way to do this, such as javascript's NaN() or IsNumeric() (was that VB...
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What is the difference between std::array and std::vector? When do you use one over other? [duplicat

...t. Creating large objects on the stack is generally frowned upon, and the extra level of indirection is usually irrelevant. (For example, if you iterate through all of the elements, the extra memory access only happens once at the start of the loop.) The vector's elements are guaranteed to be con...
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How does functools partial do what it does?

...e code more readable. re.search method's signature is: search(pattern, string, flags=0) By applying partial we can create multiple versions of the regular expression search to suit our requirements, so for example: is_spaced_apart = partial(re.search, '[a-zA-Z]\s\=') is_grouped_together = ...
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strdup() - what does it do in C?

...ed to the abbreviated way in which C and UNIX assigns words, it duplicates strings :-) Keeping in mind it's actually not part of the ISO C standard itself(a) (it's a POSIX thing), it's effectively doing the same as the following code: char *strdup(const char *src) { char *dst = malloc(strlen (...
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Test whether string is a valid integer

...aining it so I can learn a little? I gather it reads, "At the start of the string (^), a minus sign (-) is optional (?), followed by any number of characters between zero and 9, inclusive" ... and what then might the +$ mean? Thanks. – Richard T Feb 5 '10 at 21...
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Count the number of occurrences of a string in a VARCHAR field?

... The ROUND here is unnecessary. assume a string of length x with n occurrences of'value. LENGTH(description) - LENGTH( REPLACE ( description, "value", "") ) will always give you n*length("value"), diving that by length of value will always leave a whole number n. N...
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Replace non-ASCII characters with a single space

...code will insert multiple blanks per character if you feed it a UTF-8 byte string. – Mark Ransom Nov 19 '13 at 19:13 ...
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How to convert a data frame column to numeric type?

... char_fac = factor(letters[1:5]), num = 1:5, stringsAsFactors = FALSE) Let us have a glance at data.frame > d char fake_char fac char_fac num 1 a 1 1 a 1 2 b 2 2 b 2 3 c 3 3 c 3 4 d 4 ...