大约有 46,000 项符合查询结果（耗时：0.0890秒） [XML]
Removing multiple keys from a dictionary safely
... it might be more efficient to use for key in set(the_dict) & entries: and bypass the key in dict test.
– DylanYoung
Apr 15 at 15:30
add a comment
|
...
What is the difference between DSA and RSA?
It appears they are both encryption algorithms that require public and private keys. Why would I pick one versus the other to provide encryption in my client server application?
...
Python: Tuples/dictionaries as keys, select, sort
...ferent colors, e.g., 24 blue bananas, 12 green apples, 0 blue strawberries and so on.
I'd like to organize them in a data structure in Python that allows for easy selection and sorting. My idea was to put them into a dictionary with tuples as keys, e.g.,
...
Why should hash functions use a prime number modulus?
...g the "component parts" of the input (characters in the case of a string), and multiplying them by the powers of some constant, and adding them together in some integer type. So for example a typical (although not especially good) hash of a string might be:
(first char) + k * (second char) + k^2 * ...
Java LinkedHashMap get first or last entry
...ions has its own LinkedMap implementation, which has methods like firstKey and lastKey, which do what you're looking for. The interface is considerably richer.
share
|
improve this answer
...
How to change Hash values?
...my_hash[k] = v.upcase }
or, if you'd prefer to do it non-destructively, and return a new hash instead of modifying my_hash:
a_new_hash = my_hash.inject({}) { |h, (k, v)| h[k] = v.upcase; h }
This last version has the added benefit that you could transform the keys too.
...
Array_merge versus + [duplicate]
...ues in the first array will be used.
The + operator returns the right-hand array appended to the left-hand array; for keys that exist in both arrays, the elements from the left-hand array will be used, and the matching elements from the right-hand array will be ignored.
http://php.net/manual/e...
How to temporarily exit Vim and go back
How could I exit Vim, not :q , and then go back to continue editing?
10 Answers
10
...
How do I get bit-by-bit data from an integer value in C?
...( 1 << k )) >> k
Here we create a mask, apply the mask to n, and then right shift the masked value to get just the bit we want. We could write it out more fully as:
int mask = 1 << k;
int masked_n = n & mask;
int thebit = masked_n >> k;
You can read more...
What are the reasons why Map.get(Object key) is not (fully) generic
... List.equals() says that two List objects are equal if they are both Lists and have the same contents, even if they are different implementations of List. So coming back to the example in this question, according to the specification of the method is possible to have a Map<ArrayList, Something>...