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Is a Java hashmap search really O(1)?
...g claims on SO re Java hashmaps and their O(1) lookup time. Can someone explain why this is so? Unless these hashmaps are vastly different from any of the hashing algorithms I was bought up on, there must always exist a dataset that contains collisions.
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Access denied for user 'root'@'localhost' while attempting to grant privileges. How do I grant privi
...ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION |
| GRANT PROXY ON ''@'' TO 'root'@'localhost' WITH GRANT OPTION |
+---------------------------------------------------------------------+
2 rows in set (0.00 sec)
mysql> SELECT * FROM mysql.user WHERE User='root' and Host='loc...
PHP parse/syntax errors; and how to solve them
Everyone runs into syntax errors. Even experienced programmers make typos. For newcomers, it's just part of the learning process. However, it's often easy to interpret error messages such as:
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How to find out which processes are using swap space in Linux?
Under Linux, how do I find out which process is using the swap space more?
17 Answers
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How to generate a core dump in Linux on a segmentation fault?
I have a process in Linux that's getting a segmentation fault. How can I tell it to generate a core dump when it fails?
12...
What's the difference between lists and tuples?
...ave structure, lists have order.
Using this distinction makes code more explicit and understandable.
One example would be pairs of page and line number to reference locations in a book, e.g.:
my_location = (42, 11) # page number, line number
You can then use this as a key in a dictionary to s...
Difference between two DateTimes C#?
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TimeSpan span = x.ShiftEndTime.Subtract(x.ShiftStartTime) if (span.TotalHours == 24) {do...}
– abmv
May 10 '09 at 14:20
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Saving and loading objects and using pickle
...gain:
file.seek(0)
What you usually want to do though, is to use a context manager to open the file and read data from it. This way, the file will be automatically closed after the block finishes executing, which will also help you organize your file operations into meaningful chunks.
Finally, c...
Assembly code vs Machine code vs Object code?
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Machine code is binary (1's and 0's) code that can be executed directly by the CPU. If you were to open a machine code file in a text editor you would see garbage, including unprintable characters (no, not those unprintable characters ;) ).
Object code is a portion of machine cod...