Programming Articles - Page 2127 of 3363

Assume string variable a holds 'Hello' and variable b holds 'Python', then −Sr.NoOperator & DescriptionExample1+Concatenation - Adds values on either side of the operatora + b will give HelloPython2*Repetition - Creates new strings, concatenating multiple copies of the same stringa*2 will give-HelloHello3[]Slice - Gives the character from the given indexa[1] will give e4[ : ]Range Slice - Gives the characters from the given rangea[1:4] will give ell5inMembership - Returns true if a character exists in the given stringH in a will give 16not inMembership - Returns true if a character does not exist in the given stringM not in a ... Read More

You can "update" an existing string by (re)assigning a variable to another string. The new value can be related to its previous value or to a completely different string altogether. For example −Example Live Demo#!/usr/bin/python var1 = 'Hello World!' print "Updated String :- ", var1[:6] + 'Python'OutputWhen the above code is executed, it produces the following result −Updated String :- Hello Python

Python does not support a character type; these are treated as strings of length one, thus also considered a substring.ExampleTo access substrings, use the square brackets for slicing along with the index or indices to obtain your substring. For example − Live Demo#!/usr/bin/python var1 = 'Hello World!' var2 = "Python Programming" print "var1[0]: ", var1[0] print "var2[1:5]: ", var2[1:5]OutputWhen the above code is executed, it produces the following result −var1[0]: H var2[1:5]: ytho

In this article, we will go through Python's mathematical constants and how to use them. Some of the defined constants that can be utilized in a variety of mathematical operations are included in the math module. These mathematical constants return values that are equivalent to their standard defined values. The following math module constants are available in the Python programming language: Python math.e constant Python math.pi constant Python math.tau constant Python math.inf constant Python math.nan constant Python math.e constant The Euler's number, 2.71828182846, is returned by the math.e constant. Syntax math.e Return Value − It returns the ... Read More

Random numbers are used for games, simulations, testing, security, and privacy applications. Python includes following functions that are commonly used.Sr.NoFunction & Description1choice(seq)A random item from a list, tuple, or string.2randrange ([start, ] stop [, step])A randomly selected element from range(start, stop, step)3random()A random float r, such that 0 is less than or equal to r and r is less than 14seed([x])Sets the integer starting value used in generating random numbers. Call this function before calling any other random module function. Returns None.5shuffle(lst)Randomizes the items of a list in place. Returns None.6uniform(x, y)A random float r, such that x is less ... Read More

Suppose we have a string s that is formed by digits ('0' - '9') and '#'. We have to map s to one English lowercase characters as follows −Characters ('a' to 'i') are represented by ('1' to '9') respectively.Characters ('j' to 'z') are represented by ('10#' to '26#') respectively.We have to find the string formed after mapping. We are taking one assumption that a unique mapping will always exist. So if the input is like “10#11#12”, then it will be “jkab”. As 10# is j, 11# is k, 1 is a and 2 is b.To solve this, we will follow ... Read More

Suppose we have one ‘head’ which is a reference node to a singly-linked list. The value of each node present in the linked list is either 0 or 1. This linked list stores the binary representation of a number. We have to return the decimal value of the number present in the linked list. So if the list is like [1, 0, 1, 1, 0, 1]To solve this, we will follow these steps −x := convert the list elements into an arraythen reverse the list xans := 0, and temp := 1for i in range i := 0, to size ... Read More

Suppose we have one 2D grid of size m x n. We have another variable k. We have to shift the grid k times. The shift operation will be as followsElement at grid G[i, j] moves to G[i, j + 1]Element at grid G[i, n – 1] moves to G[i + 1, 0]Element at grid G[m - 1, n – 1] moves to G[0, 0]So if the grid is like −123456789The output will be −912345678To solve this, we will follow these steps −The shift operation will take the matrix as inputn = number of rows, m := number of columns, ... Read More

Suppose there are some chips, the i-th chip is at present at position chips[i]. We can perform any of the two following types of operations any many numbers of times as we want (possibly zero) on any chip −Move the i-th chip by 2 units to the left side or to the right side with a cost of 0.Move the i-th chip by 1 unit to the left side or to the right side with a cost of 1.Initially, there can be two or more chips. We have to return the minimum cost needed to move all the chips to ... Read More

Suppose we have an array A of integers, we have to modify the array in the following way −We can choose an i and replace the A[i] with -A[i], and we will repeat this process K times. We have to return the largest possible sum of the array after changing it in this way.So, if the array A = [4, 2, 3], and K = 1, then the output will be 5. So choose indices 1, the array will become [4, -2, 3]To solve this, we will follow these steps −Sort the array Afor i in range 0 to length ... Read More