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If you want to get an inversion of only first 16 bits of a number, you can take a xor of that number with 65535(16 1s in binary). examplea = 3 # 11 in binary b = a ^ 65535 print(bin(b))OutputThis will give the output −0b1111111111111100
JShell is a command-line tool that allows us to enter Java statements (simple statements, compound statements, or even full methods and classes), evaluates it and prints the result.Forward references are commands that refer to methods, variables, or classes that don't exist in any code we have typed in JShell. As code entered and evaluated sequentially in JShell, these forward references have temporarily unresolved. JShell supports forward references in method bodies, return types, parameter types, variable types, and within a class.In the below code snippet, created a method forwardReference() in Jshell. This method can't be invoked until the variable is declared. If we are trying to attempt to call this method, it throws a ... Read More
You can do Python operator overloading with multiple operands just like you would do it for binary operators. For example, if you want to overload the + operator for a class, you'd do the following −Exampleclass Complex(object): def __init__(self, real, imag): self.real = real self.imag = imag def __add__(self, other): real = self.real + other.real imag = self.imag + other.imag return Complex(real, imag) def display(self): print(str(self.real) + " + " + str(self.imag) + "i") a = Complex(10, 5) b = Complex(5, 10) c = Complex(2, 2) d = a + b + c d.display()OutputThis will give the output −17 + 17i
The help method in the interpreter is very useful for such operations. It provides a rich set of special inputs that you can give to it to get information about the different aspects of the language. Forgetting operator lists, here are some of the commands you can use:All operators>>> help('SPECIALMETHODS')Basic operators>>> help('BASICMETHODS')Numeric operators>>> help('NUMBERMETHODS')Other than operators you can also get attribute methods, callable methods, etc using −>>> help('MAPPINGMETHODS') >>> help('ATTRIBUTEMETHODS') >>> help('SEQUENCEMETHODS1') >>> help('SEQUENCEMETHODS2') >>> help('CALLABLEMETHODS')
The += operator is syntactic sugar for object.__iand__() function. From the python docs:These methods are called to implement the augmented arithmetic assignments (+=, -=, *=, @=, /=, //=, %=, **=, =, &=, ^=, |=). These methods should attempt to do the operation in-place (modifying self) and return the result (which could be, but does not have to be, self).ExampleSo when you do something like −a = 6 # 110 in binary b = 5 # 101 in binary a &= b # a changes to and of 110 and 101, ie, 100, ie, 4 print(a)OutputThis will give the output −15a ... Read More
Suppose we have the root of a binary tree, each node in the tree has a unique value. After removing all nodes with a value in to_delete, we are left with a forest. We have to find the roots of the trees in the remaining forest. So if the input is likeif the to_delete array is like [3, 5], then the output will beTo solve this, we will follow these steps −Define an array resDefine a method solve(), this will take node, to_delete array and a Boolean type info to which is telling that the node is root or not. ... Read More
The += operator is syntactic sugar for object.__iadd__() function. From the python docs:These methods are called to implement the augmented arithmetic assignments (+=, -=, *=, @=, /=, //=, %=, **=, =, &=, ^=, |=). These methods should attempt to do the operation in-place (modifying self) and return the result (which could be, but does not have to be, self).ExampleSo when you do something like −a = 5 b = 10 a += b print(a)OutputThis will give the output −15a is being modified in place here. You can read more about such operators on https://docs.python.org/3/reference/datamodel.html#object.__iadd__.The =+ operator is the same as ... Read More
You can do this by iterating over the dictionary and filtering out zero values first. Then take the sum of the filtered values. Finally, divide by the number of these filtered values. examplemy_dict = {"foo": 100, "bar": 0, "baz": 200} filtered_vals = [v for _, v in my_dict.items() if v != 0] average = sum(filtered_vals) / len(filtered_vals) print(average)OutputThis will give the output −150.0You can also use reduce but for a simple task such as this, it is an overkill. And it is also much less readable than using a list comprehension.
The easiest and most readable way to access nested properties in a Python dict is to use for loop and loop over each item while getting the next value, until the end. exampledef getFromDict(dataDict, mapList): for k in mapList: dataDict = dataDict[k] return dataDict a = { 'foo': 45,'bar': { 'baz': 100,'tru': "Hello" } } print(getFromDict(a, ["bar", "baz"]))OutputThis will give the output −100
If you have a dict with string-integer mappings, you can use the max method on the dictionary's item pairs to get the largest value. exampled = { 'foo': 100, 'bar': 25, 'baz': 360 } print(max(k for k, v in d.items()))OutputThis will give the output −foofoo is largest in alphabetical order.