In this problem, we are given a 2D array. Our task is to print all the elements of the array starting from the first row, from left to right, then right to left in the next row and again from left to right and so on.Let’s take an example to understand the problem.Input: array = {    {2, 5}    {4, 9} } Output: 2 5 9 4To solve this problem, we will print elements in the given direction (LtoR and RtoL) of a row. And a flag element to show the direction of printing will switch after every iteration.This ... Read More

In this problem, we are given a matrix. Our task is to print the matrix in reverse waveform in a single line.This example will make the problem clear, Input:    1 4 6 11    2 5 8 54    7 9 3 43    1 7 4 34 Output: 11 54 43 34 4 3 8 6 4 5 9 7 1 7 2 1To solve this problem, we have to print the reverse waveform of our matrix and for this, we will print the elements of the last column in the downward direction and then second-last column’s elements ... Read More

In this problem, we are given two numbers K and D. Our task is to print a number of k digits and which has digital root equal to D.Digital Root is a single-digit value which is the result of the recursive addition of the digits of the number till the one a single-digit number is reached. Also known as a digital sum.Let’s take an example to understand the problem, Input: D = 5 , K = 6 Output: 60000To solve this problem, we will be using trials of zero’s after the number D. Our number will be {D000..(k-1 times)}. This ... Read More

In this problem, we are given a number n. Our task is to print the largest number less than n such that all its digits are distinct.Let’s take an example to understand the problemInput: n = 2332 Output: 2319To solve this problem, we reverse the count of the numbers i.e. from n to 0. And check for number with distinct digits, if the current count values satisfy the condition print it and end the loop. Otherwise continue to loop. The max number of times the loop will run is always less than n.ExampleProgram to implement our solutions,  Live Demo#include ... Read More

Loop control statements change execution from its normal sequence. When execution leaves a scope, all automatic objects that were created in that scope are destroyed.Python supports the following control statements. Click the following links to check their detail.Let us go through the loop control statements brieflySr.NoOperator & Description1break statementTerminates the loop statement and transfers execution to the statement immediately following the loop.2continue statementCauses the loop to skip the remainder of its body and immediately retest its condition prior to reiterating.3pass statementThe pass statement in Python is used when a statement is required syntactically but you do not want any command ... Read More

Python’s membership operators test for membership in a sequence, such as strings, lists, or tuples. There are two membership operators as explained below −Sr.NoOperator & DescriptionExample1inEvaluates to true if it finds a variable in the specified sequence and false otherwise.x in y, here in results in a 1 if x is a member of sequence y.2not inEvaluates to true if it does not finds a variable in the specified sequence and false otherwise.x not in y, here not in results in a 1 if x is not a member of sequence y.Example Live Demo#!/usr/bin/python a = 10 b = 20 list ... Read More

Sometimes, you may need to perform conversions between the built-in types. To convert between types, you simply use the type name as a function.There are several built-in functions to perform conversion from one data type to another. These functions return a new object representing the converted value.Sr.No.Function & Description1int(x [, base])Converts x to an integer. base specifies the base if x is a string.2long(x [, base] )Converts x to a long integer. base specifies the base if x is a string.3float(x)Converts x to a floating-point number.4complex(real [, imag])Creates a complex number.5str(x)Converts object x to a string representation.6repr(x)Converts object x to ... Read More

Python's dictionaries are kind of hash table type. They work like associative arrays or hashes found in Perl and consist of key-value pairs. A dictionary key can be almost any Python type, but are usually numbers or strings. Values, on the other hand, can be any arbitrary Python object.ExampleDictionaries are enclosed by curly braces ({ }) and values can be assigned and accessed using square braces ([]). For example − Live Demo#!/usr/bin/python dict = {} dict['one'] = "This is one" dict[2] = "This is two" tinydict = {'name': 'john', 'code':6734, 'dept': 'sales'} print dict['one'] # Prints value for 'one' key print ... Read More

A tuple is another sequence data type that is similar to the list. A tuple consists of a number of values separated by commas. Unlike lists, however, tuples are enclosed within parentheses.ExampleThe main differences between lists and tuples are: Lists are enclosed in brackets ( [ ] ) and their elements and size can be changed, while tuples are enclosed in parentheses ( ( ) ) and cannot be updated. Tuples can be thought of as read-only lists. For example − Live Demo#!/usr/bin/python tuple = ( 'abcd', 786 , 2.23, 'john', 70.2 ) tinytuple = (123, 'john') print tuple # Prints ... Read More

Lists are the most versatile of Python's compound data types. A list contains items separated by commas and enclosed within square brackets ([]). To some extent, lists are similar to arrays in C. One difference between them is that all the items belonging to a list can be of different data type.ExampleThe values stored in a list can be accessed using the slice operator ([ ] and [:]) with indexes starting at 0 in the beginning of the list and working their way to end -1. The plus (+) sign is the list concatenation operator, and the asterisk (*) is ... Read More