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Will using 'var' affect performance?
...e it can't figure out what type you intended to use, you'll get a compiler error.
The only trick is that var will infer an exact type where you may have chosen an Interface or parent type if you were to set the type manually.
Update 8 Years Later
I need to update this as my understanding has change...
How to use the PI constant in C++
... constant.
– Timmmm
Apr 3 '14 at 15:05
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show 8 more comments
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Add an element to an array in Swift
...
Error: Value of type 'Array<Element>' has no member 'appendContentsOf'
– Dani Kemper
Oct 17 '18 at 22:55
...
‘ld: warning: directory not found for option’
... this:
Click on your project (targets)
Click on Build Settings
if your error includes the -L flag, then delete the values in Library Search Paths
if your error includes the -F flag, then delete the values in Framework Search Paths
And regarding the second error, sorry i can't help you out w...
Floating point vs integer calculations on modern hardware
...;
# else
struct timeval tv;
if(gettimeofday(&tv, 0) < 0) {
perror("oops");
}
return (double)tv.tv_sec + (0.000001 * (double)tv.tv_usec);
# endif
}
template< typename Type >
void my_test(const char* name) {
Type v = 0;
// Do not use constants or repeating values
// t...
simple HTTP server in Java using only Java SE API
...
If you're using Eclipse and get an error like "Access restriction: The type HttpExchange is not accessible due to restriction on required library ...", stackoverflow.com/a/10642163 tells how to disable that access check.
– Samuli Pahaoja
...
How to get all subsets of a set? (powerset)
...3,) (1,2) (1,3) (2,3) (1,2,3)"
s = list(iterable)
return chain.from_iterable(combinations(s, r) for r in range(len(s)+1))
Output:
>>> list(powerset("abcd"))
[(), ('a',), ('b',), ('c',), ('d',), ('a', 'b'), ('a', 'c'), ('a', 'd'), ('b', 'c'), ('b', 'd'), ('c', 'd'), ('a', 'b', 'c'...
Windows batch: formatted date into variable
...ll instead.
– Joey
Oct 17 '13 at 20:05
1
Variables that will be set: Year, Month, Day, Hour, Minu...
Count occurrences of a char in plain text file
... 1100000 occurences of the searched character:
real 0m0.089s
user 0m0.057s
sys 0m0.027s
Time for Vereb answer with echo, cat, tr and bc for the same file:
real 0m0.168s
user 0m0.059s
sys 0m0.115s
Time for Rob Hruska answer with tr, sed and wc for the same file:
real 0m0.465s
u...
Iterating over every two elements in a list
...ad a list that had not even amount of numbers in it, it would get an index error. Solved it with a try: except:
– Hans de Jong
Oct 20 '14 at 9:39
...