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Is sizeof(bool) defined in the C++ language standard?
...r, since 0xbadf00d asked about the standard, not some specific/arbitrarily selected compiler implementation, right?
– Christopher Creutzig
Dec 12 '13 at 22:27
13
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Why can't I forward-declare a class in a namespace using double colons?
...). Essentially, it must be one of class identifier;, struct identifier; or union identifier; where identifer is the common lexical definition in [lex.name]:
identifier:
identifier-nondigit
identifier identifier-nondigit
identifier digit
identifier-nondigit:
nondigit
universal-character-n...
Generating all permutations of a given string
... for (int i = 0; i < n; i++)
permutation(prefix + str.charAt(i), str.substring(0, i) + str.substring(i+1, n));
}
}
(via Introduction to Programming in Java)
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improv...
How to loop backwards in python? [duplicate]
...th = len(text)-1
# loop through the string in reverse and append each character
# deprecate the length index
while length>=0:
txet += "%s"%text[length]
length-=1
return txet
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...
Determine version of Entity Framework I am using?
...";
var assemblies = System.AppDomain.CurrentDomain.GetAssemblies().Select(x => x.FullName).ToList();
foreach(var asm in assemblies)
{
var fragments = asm.Split(new char[] { ',', '{', '}' }, StringSplitOptions.RemoveEmptyEntries).Select(x=> x.Trim()).ToList()...
In C, do braces act as a stack frame?
...stack frame. Otherwise, you would not be able to do something like this:
char var = getch();
{
char next_var = var + 1;
use_variable(next_char);
}
If curly braces caused a true stack push/pop (like a function call would), then the above code would not compile because the ...
Concatenate multiple result rows of one column into one, group by another column [duplicate]
...Simpler with the aggregate function string_agg() (Postgres 9.0 or later):
SELECT movie, string_agg(actor, ', ') AS actor_list
FROM tbl
GROUP BY 1;
The 1 in GROUP BY 1 is a positional reference and a shortcut for GROUP BY movie in this case.
string_agg() expects data type text as input. Other ...
Is it better to reuse a StringBuilder in a loop?
...0) is far and away the most efficient answer. StringBuilder is backed by a char array and is mutable. At the point .toString() is called, the char array is copied and is used to back an immutable string. At this point, the mutable buffer of StringBuilder can be re-used, simply by moving the insertio...
How to read a single character from the user?
Is there a way of reading one single character from the user input? For instance, they press one key at the terminal and it is returned (sort of like getch() ). I know there's a function in Windows for it, but I'd like something that is cross-platform.
...
Do I cast the result of malloc?
...ther points are also trivial, if you use the variable in your malloc call: char **foo = malloc(3*sizeof(*foo)); if quite full-proof: 3 pointers to char pointers. then loop, and do foo[i] = calloc(101, sizeof(*(foo[i])));. Allocate array of 101 chars, neatly initialized to zeroes. No cast needed. cha...