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Count the number of occurrences of a string in a VARCHAR field?
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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...
How do I properly compare strings in C?
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You can't (usefully) compare strings using != or ==, you need to use strcmp:
while (strcmp(check,input) != 0)
The reason for this is because != and == will only compare the base addresses of those strings. Not the contents of the strings themselves.
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How do I get the last character of a string?
How do I get the last character of a string?
11 Answers
11
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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) + " ...
Find and extract a number from a string
I have a requirement to find and extract a number contained within a string.
29 Answers
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Haskell: Lists, Arrays, Vectors, Sequences
... up performance tends to come from [Char] which the prelude has aliased as String. Char lists are convient, but tend to run on the order of 20 times slower than C strings, so feel free to use Data.Text or the very fast Data.ByteString. I'm sure there are other sequence oriented libraries I'm not t...
What is the purpose of std::make_pair vs the constructor of std::pair?
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int main() {
MyClass<int> my_class(1);
}
then:
g++-8 -Wall -Wextra -Wpedantic -std=c++17 main.cpp
compiles happily, but:
g++-8 -Wall -Wextra -Wpedantic -std=c++14 main.cpp
fails with:
main.cpp: In function ‘int main()’:
main.cpp:13:13: error: missing template arguments before...
snprintf and Visual Studio 2010
...tes at most buf_size - 1 characters to a buffer. The resulting
character string will be terminated with a null character, unless
buf_size is zero. If buf_size is zero, nothing is written and
buffer may be a null pointer. The return value is the number of
characters that would have been writt...
What does the explicit keyword mean?
...cidental construction that can hide bugs.
Contrived example:
You have a MyString(int size) class with a constructor that constructs a string of the given size. You have a function print(const MyString&), and you call print(3) (when you actually intended to call print("3")). You expect it to p...
Avoid trailing zeroes in printf()
...01357
breaks it.
What you can do is to sprintf("%.20g") the number to a string buffer then manipulate the string to only have N characters past the decimal point.
Assuming your number is in the variable num, the following function will remove all but the first N decimals, then strip off the trai...