大约有 47,000 项符合查询结果（耗时：0.0522秒） [XML]
What is the difference between & and && in Java?
...& operator in Java is used for verifying whether both its boolean operands are true , and the & operator is used to do Bit-wise operations on two integer types.
...
What would cause an algorithm to have O(log n) complexity?
My knowledge of big-O is limited, and when log terms show up in the equation it throws me off even more.
6 Answers
...
Adding a column to a data.frame
...xt, [[.data.frame.
Data frames can be indexed in several modes. When [ and [[ are used with a single vector index (x[i] or x[[i]]), they index the data frame as if it were a list.
my.dataframe["new.col"] <- a.vector
my.dataframe[["new.col"]] <- a.vector
The data.frame method for $, ...
Why does 2 mod 4 = 2?
...ion. My term does not start for two more weeks so I can't ask a professor, and the suspense would kill me.
19 Answers
...
calculating the difference in months between two dates
... figure out a formula for total months difference. Variable days per month and leap years keep throwing me off. How can I get TotalMonths ?
...
O(nlogn) Algorithm - Find three evenly spaced ones within binary string
I had this question on an Algorithms test yesterday, and I can't figure out the answer. It is driving me absolutely crazy, because it was worth about 40 points. I figure that most of the class didn't solve it correctly, because I haven't come up with a solution in the past 24 hours.
...
How to iterate over arguments in a Bash script
I have a complex command that I'd like to make a shell/bash script of. I can write it in terms of $1 easily:
8 Answers
...
Boolean operators && and ||
According to the R language definition , the difference between & and && (correspondingly | and || ) is that the former is vectorized while the latter is not.
...
Bomb dropping algorithm
... simple sub-problem.
There are 2 parts to the explanation, the algorithm, and the reason the algorithm
provides an optimal solution. The first won't make sense without the second, so I'll
start with the why.
If you think of bombing the rectangle (assume a big rectangle - no edge cases yet)
you...
Common programming mistakes for Clojure developers to avoid [closed]
What are some common mistakes made by Clojure developers, and how can we avoid them?
8 Answers
...