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Count the number of occurrences of a character in a string in Javascript
I need to count the number of occurrences of a character in a string.
33 Answers
33
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Should I inherit from std::exception?
...a C-String or a std::string to the constructor that will be returned (as a char const*) when what() is called.
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What's the point of malloc(0)?
...que pointer that can be passed to free"), but if you're treating this as a char*, that may give you an invalid, non-terminated char. It could be dangerous to rely on this in cross-platform situations.
– Reed Copsey
Jan 7 '10 at 17:51
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What is a NullReferenceException, and how do I fix it?
... to find out where the reference is or isn't set, right-click its name and select "Find All References". You can then place a breakpoint at every found location and run your program with the debugger attached. Every time the debugger breaks on such a breakpoint, you need to determine whether you exp...
What's the recommended approach to resetting migration history using Django South?
...ps, so make sure you either run the other two lines for all apps or delete selectively).
The convert_to_south call at the end makes a new migration and fake-applies it (since your database already has the corresponding tables). There's no need to drop all the app tables during the process.
He...
Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
Difference between ActionBarSherlock and ActionBar Compatibility
...ar (CAB) a menu that takes over the action bar, used for example for multi select (http://developer.android.com/design/patterns/new-4-0.html) This is a ICS feature (!) For this, an implementation of the ActionMode class (introduced in API level 11) had to be introduced into the ActionbarSherlock lib...
What are the Dangers of Method Swizzling in Objective-C?
... class_getInstanceMethod(class, original);
if (method) {
const char *type = method_getTypeEncoding(method);
imp = class_replaceMethod(class, original, replacement, type);
if (!imp) {
imp = method_getImplementation(method);
}
}
if (imp &&...
Finding the max value of an attribute in an array of objects
...nput in a array):
var maxA = a.reduce((a,b)=>a.y>b.y?a:b).y; // 30 chars time complexity: O(n)
var maxB = a.sort((a,b)=>b.y-a.y)[0].y; // 27 chars time complexity: O(nlogn)
var maxC = Math.max(...a.map(o=>o.y)); // 26 chars time complexity: >O(2n)
editable example her...
How do I read an entire file into a std::string in C++?
...os_type fileSize = ifs.tellg();
ifs.seekg(0, ios::beg);
vector<char> bytes(fileSize);
ifs.read(bytes.data(), fileSize);
return string(bytes.data(), fileSize);
}
This solution resulted in about 20% faster execution times than the other answers presented here, when taking the...