How to get rows and columns count of a 2D array in Java?
Well you probably want array_name.length for getting the count of the rows and array_name[0].length for the columns. That is, if you defined your array like so:
arrays
Using cin to input a single letter into a char
You are not inputting or outputting the characters correctly. char letter[2] is an array of 2 characters, not a single character. You want char letter. Further, you are outputting letter[2], which is the third element of an array that only has two values (indexing in C++ starts from 0; the first element is letter[0] and … Read more
What is the best way to convert an array to a hash in Ruby
NOTE: For a concise and efficient solution, please see Marc-André Lafortune’s answer below. This answer was originally offered as an alternative to approaches using flatten, which were the most highly upvoted at the time of writing. I should have clarified that I didn’t intend to present this example as a best practice or an efficient … Read more
Best way to “push” into C# array
array.push is like List<T>.Add. .NET arrays are fixed-size so you can’t actually add a new element. All you can do is create a new array that is one element larger than the original and then set that last element, e.g. EDIT: I’m not sure that this answer actually applies given this edit to the question: … Read more
Getting error “array bound is not an integer constant before ‘]’ token”
In C++, the size of an array must be a constant known at compile-time. You’ll get an error if that isn’t the case. Here, you have Notice that this->cap isn’t a constant known at compile-time, since it depends on how big cap is. If you want to have a variably-sized array whose size is determined … Read more
PHP array delete by value (not key)
Using array_search() and unset, try the following: array_search() returns the key of the element it finds, which can be used to remove that element from the original array using unset(). It will return FALSE on failure, however it can return a false-y value on success (your key may be 0 for example), which is why … Read more
Hashing arrays in Python
Just try it: So you can get hash of tuple and frozenset since the are immutable, and you can’t do it for list and set because they are mutable.
The difference between char * and char[] [duplicate]
The most straightforward answer is: The difference here is that will place Hello world in the read-only parts of the memory and making s a pointer to that, making any writing operation on this memory illegal. While doing: puts the literal string in read-only memory and copies the string to newly allocated memory on the … Read more
How to add an element at the end of an array?
I want to know how to add or append a new element to the end of an array. Is any simple way to add the element at the end? I know how to use a StringBuffer but I don’t know how to use it to add an element in an array. I prefer it without … Read more
Array to Hash Ruby
That’s it. The * is called the splat operator. One caveat per @Mike Lewis (in the comments): “Be very careful with this. Ruby expands splats on the stack. If you do this with a large dataset, expect to blow out your stack.” So, for most general use cases this method is great, but use a … Read more