Python List Full Infromation with Interview questions

 #LIST --List one of the data type in python

#A List is a collection of items stored in a single variable.

#list can store multiple values with comma speciation

#list we can identify  begins with an opening square bracket and

#ends with a closing square bracket, []

#A list value looks like this: ['cat', 'bat', 'rat', 'elephant'].

# list is Ordered,Mutable (changeable),Allow duplicates ,Can store different data types

#

animals=["cat","rat","Cow","Hen","horse","dog"]

print("Name of the animals Is",animals)

#in List data type we can store String values ,Int values ,flote values anything

animals_digits=["cat","0","rat","1","Cow","2","Hen","3","horse","4","dog","5"]

print("Name of the animals Is",animals_digits)

#Just as an index can get a single value from a list,

#List value Index --> it will Index first value from list

print(animals_digits[0])

print(animals_digits[1]) #it will Index 2 value from list

print(animals_digits[2]) #it will Index 3 value from list

print(animals_digits[-1]) #it will Negative Index Last value from list

print(animals_digits[-2])

#a slice can get several values from a list, in the form of a new list

print(animals_digits[0:4]) # Get 0,1,2,3 values from List # means 0-cat,1-0,2-rat,3-1

text = "HELLO"

print(text[1])     # E

print(text[1:2])   # E (but type is different!)

text = "PYTHON"

print(text[::2]) # Result is PTO Means Step = 2 (skip one)

Blak = "Mahen"

print(Blak[1:10])

#-------------------------------------------------

text = "HELLO"

print(text[1:2] == text[1]) # Result should be True

# Both are 'E', but types conceptually differ (still equal)

#---------------------------------------------------

nums = [10, 20, 30, 40]

print(nums[-3:-1])

#While Slicing start included, stop excluded

#Changing the Values in List

nums[0]=200 # Old Nums [10, 20, 30, 40]

print(nums) #Result should be [200, 20, 30, 40]

#List Concatenation(+) and List Replication(*)

value=[1, 2, 3] + ['A', 'B', 'C']

print(value) # Result is:-[1, 2, 3, 'A', 'B', 'C']

value=[1,2,3]*2

print(value) # Result  Is:[1, 2, 3, 1, 2, 3]

#Removing Values from Lists with del Statements

del value[1] # Result  Is:[1, 2, 3, 1, 2, 3]

print(value) #Result [1, 3, 1, 2, 3]

#Adding Values to Lists with the append() and insert() Methods

# sy : string.append(value)

s1=[1,2,3,'python','java']

s1.append('C++')

print(s1) #[1, 2, 3, 'python', 'java', 'C++']

#Insert Method SY: Insert(index,object)

str=[1,2,3,'python','java']

str.insert(2,'C') #[1, 2, 'C', 3, 'python', 'java']

print(str)

#Removing Values from Lists with remove()

str1=[1,2,3,'python','java']

str1.remove(2)

print(str1) # result [1, 3, 'python', 'java']

#Sorting the Values in a List with the sort() Method

str2=[0,5,13,9,6,20,15]

str2.sort() # result [0, 5, 6, 9, 13, 15, 20]

print(str2)

str2.sort(reverse=True) # result [20, 15, 13, 9, 6, 5, 0]

print(str2)

str3=[1, 3, 2, 4, 'Alice', 'Bob']

#str3.sort()

print(str3) #TypeError: '<' not supported between instances of 'str' and 'int'

#A list value is a mutable data type: It can have values added, removed, or changed.

#List Copy

l1=str1.copy() #str1 copy into l1

print(l1)

#========== real Time Interview question ===============

#Find the largest Number in given LIST

Numbers=[10,20,30,50,60] # Largest Number is 60

print(max(Numbers))  #->60

#Find the second-largest number in List

Numbers=[10,20,70,50,90,15,20,80,20,25,100]

Numbers.sort(reverse=False)

print(Numbers[-2])  # result 90

# Remove Duplicates in Given List

Number1=[10,20,70,50,90,15,20,80,20,25,100]

unique=list(set(Number1))

print(unique) #-->[100, 70, 10, 15, 80, 50, 20, 25, 90]

# List Unpacking

a, b, c = [10, 20, 30]

print(a, b, c) #

print(a+b)

print(a)

#Reveses list Using Reverse keyword without using reverse key word

nums = [1,2,3,4]

nums.sort(reverse=True)

print(nums)

print(nums[::1])#-Result [4, 3, 2, 1]