Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Economics & Finance
Finding the length of a list without using built-in functions like len() is a common programming exercise. We can achieve this using several creative approaches including loops, mapping, and recursive methods. So, if the input is like nums = [5, 7, 6, 4, 6, 9, 3, 6, 2], then the output will be 9. Method 1: Using map() and sum() We can map each element to 1 and then sum the results ? def find_length_map(nums): return sum(map(lambda x: 1, nums)) nums = [5, 7, 6, 4, 6, 9, 3, 6, ... Read More
In Python, you can find the sum of all odd elements in an existing List using one of the following ways: Using List Comprehension Using a Loop Using filter() Function Using List Comprehension The List Comprehension method allows us to create ... Read More
List slicing in Python provides a simple and efficient way to reverse a list using the slice notation [::-1]. This approach creates a new list with elements in reverse order without modifying the original list. Understanding List Slicing Syntax List slicing takes three parameters separated by colons: [start:end:step] start − Starting index (default: 0) end − Ending index (default: length of list) step − Step size (default: 1) For reversing, we use [::-1] where: Empty start and end means include entire list -1 step means move backwards through the list ... Read More
Creating a list with n elements from 1 to n is a common task in Python. There are several efficient approaches using list comprehension, range() with list(), and other methods. So, if the input is like n = 5, then the output will be [1, 2, 3, 4, 5] Using List Comprehension List comprehension provides a concise way to create lists by iterating over a range ? def solve(n): return [i for i in range(1, n+1)] n = 5 result = solve(n) print(result) [1, 2, 3, 4, ... Read More
Finding the "better divisor" of a number involves comparing divisors based on their digit sum. A divisor with a higher digit sum is considered better, and if digit sums are equal, the smaller number wins. Problem Definition Given a number n, we need to find the best divisor based on these criteria ? The divisor with the highest sum of digits is better If digit sums are equal, the smaller divisor is better Example For n = 180, the divisors are [1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, ... Read More
Suppose we have a set of heights where there may be some duplicate entries. We need to find the average of distinct entries from these heights. So, if the input is like heights = [96, 25, 83, 96, 33, 83, 24, 25], then the output will be 52.2 because the unique elements are [96, 25, 83, 33, 24], so sum is 96 + 25 + 83 + 33 + 24 = 261, average is 261/5 = 52.2. Algorithm To solve this problem, we will follow these steps ? h_set := a set from heights to ... Read More
In Python, we can extract elements at specific positions from a list. To find only even indexed elements (elements at positions 0, 2, 4, etc.), we can use list slicing techniques. So, if the input is like nums = [5, 7, 6, 4, 6, 9, 3, 6, 2], then the output will be [5, 6, 6, 3, 2] (elements at indices 0, 2, 4, 6, 8). Understanding Even vs Odd Indices Let's first clarify the index positions in our example list ? nums = [5, 7, 6, 4, 6, 9, 3, 6, 2] # ... Read More
Converting a complex number to polar coordinates involves finding the magnitude (radius) and phase angle. For a complex number x + yj, the radius is sqrt(x² + y²) and the angle is measured counter-clockwise from the positive x-axis. Python's cmath module provides built-in functions: abs() for magnitude and phase() for the angle in radians. Syntax import cmath magnitude = abs(complex_number) angle = cmath.phase(complex_number) Example Let's convert the complex number 2+5j to polar coordinates ? import cmath def convert_to_polar(c): return (abs(c), cmath.phase(c)) c = 2+5j ... Read More
Python's itertools.permutations() function generates all permutations of a specified length from a string. A permutation is an arrangement of elements where order matters. Syntax itertools.permutations(iterable, r) Parameters: iterable − The input string or sequence r − Length of each permutation (optional, defaults to full length) Example Let's generate all permutations of size 3 from the string "HELLO" ? from itertools import permutations def solve(s, r): vals = list(permutations(s, r)) result = [] for x in vals: ... Read More
Looking at this article, I notice there's a topic mismatch - it's about PHP but the instructions are for Python articles. However, I'll improve the PHP article following the general improvement guidelines. The mb_list_encodings() function in PHP returns an array of all supported character encodings available in the multibyte string extension. This function is part of PHP's mbstring extension and is available in PHP 5.0.0 and higher versions. Syntax array mb_list_encodings() Parameters The mb_list_encodings() function takes no parameters. Return Value This function returns a numerically indexed array containing the names of ... Read More