How to dynamically allocate arrays in C++

for arrays (which is what you want) or for single elements. But it’s more simple to use vector, or use smartpointers, then you don’t have to worry about memory management. L.data() gives you access to the int[] array buffer and you can L.resize() the vector later. L.get() gives you a pointer to the int[] array.

Which is the difference between Long.valueOf(0) and 0L in Java?

Nothing. will undergo autoboxing. The compiler replaces it with: You can see this if you decompile your class, e.g. using javap. Decompiles to: So how it is better initialize a variable, considering memory consumption and time complexity? Because they are semantically identical, the memory consumption and time complexity is also identical. Instead, focus on what is actually … Read more

How to merge branch to master?

If you want to merge your branch to master on remote, follow the below steps: push your branch say ‘br-1’ to remote using git push origin br-1. switch to master branch on your local repository using git checkout master. update local master with remote master using git pull origin master. merge br-1 into local master using git merge br-1. … Read more

What does (~0L) mean?

0L is a long integer value with all the bits set to zero – that’s generally the definition of 0. The ~ means to invert all the bits, which leaves you with a long integer with all the bits set to one. In two’s complement arithmetic (which is almost universal) a signed value with all bits set to one is -1. The reason for … Read more

What does href expression do?

An <a> element is invalid HTML unless it has either an href or name attribute. If you want it to render correctly as a link (ie underlined, hand pointer, etc), then it will only do so if it has a href attribute. Code like this is therefore sometimes used as a way of making a link, but without having to provide an actual … Read more

numpy array: IndexError: too many indices for array

Numpy ndarrays are meant for all elements to have the same length. In this case, your second array doesn’t contain lists of the same length, so it ends up being a 1-D array of lists, as opposed to a “proper” 2-D array. From the Numpy docs on N-dimensional arrays: An ndarray is a (usually fixed-size) multidimensional … Read more

What is *(uint32_t*)?

uint32_t is a numeric type that guarantees 32 bits. The value is unsigned, meaning that the range of values goes from 0 to 232 – 1. This declares a pointer of type uint32_t*, but the pointer is uninitialized, that is, the pointer does not point to anywhere in particular. Trying to access memory through that pointer will cause … Read more

How do I sort a dictionary by value?

Python 3.7+ or CPython 3.6 Dicts preserve insertion order in Python 3.7+. Same in CPython 3.6, but it’s an implementation detail. or Older Python It is not possible to sort a dictionary, only to get a representation of a dictionary that is sorted. Dictionaries are inherently orderless, but other types, such as lists and tuples, are … Read more

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