Python Program To Remove Duplicates From List

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Python Program To Remove Duplicates From List

“How to remove duplicates from list” is a popular question and very frequently asked in interviews also. There are so different methods to remove duplicate values for list. Here we are going to cover the general methods. First method is using set properties, and another that using for loop in a simple way. The last one is using dictionary.

 

 

 

01. Method: Using Set Properties.

01. Example

Apply on string list.

cars = ['Lamborghini','Honda', 'Jeep', 'Honda', 'BMW','Hyundai', 'Hyundai', 'BMW', 'Ford']
print("Array: n", cars)
print("nnArray After Removing Duplicate:n",list(set(cars)))

Output:

Array: 
 ['Lamborghini', 'Honda', 'Jeep', 'Honda', 'BMW', 'Hyundai', 'Hyundai', 'BMW', 'Ford']


Array After Removing Duplicate:
 ['Jeep', 'Ford', 'Honda', 'Lamborghini', 'Hyundai', 'BMW']

 

02. Example

Apply on numeric list.

numbers = [23, 45, 34, 78, 23, 78, 12, 89, 45, 34, 54, 34]

print("Array: n", numbers)
print("nnArray After Removing Duplicate:n",list(set(numbers)))

Output:

Array: 
 [23, 45, 34, 78, 23, 78, 12, 89, 45, 34, 54, 34]


Array After Removing Duplicate:
 [34, 12, 45, 78, 54, 23, 89]

 

02. Method: Using For Loops.

01. Example

Apply on string list.

def removeDuplicate(duplicate):
 data = []
 for num in duplicate:
  if num not in data:
   data.append(num)
 return data
 

cars = ['Lamborghini','Honda', 'Jeep', 'Honda', 'BMW','Hyundai', 'Hyundai', 'BMW', 'Ford']
print("Array: n", cars)

result = removeDuplicate(cars) 
print("nnArray After Removing Duplicate:n",result)

Output:

Array: 
 ['Lamborghini', 'Honda', 'Jeep', 'Honda', 'BMW', 'Hyundai', 'Hyundai', 'BMW', 'Ford']


Array After Removing Duplicate:
 ['Lamborghini', 'Honda', 'Jeep', 'BMW', 'Hyundai', 'Ford']

 

02. Example

Apply on numeric list.

def removeDuplicate(duplicate):
 data = []
 for num in duplicate:
  if num not in data:
   data.append(num)
 return data
 

numbers = [23, 45, 34, 78, 23, 78, 12, 89, 45, 34, 54, 34]
print("Array: n", numbers)

result = removeDuplicate(numbers) 
print("nnArray After Removing Duplicate:n",result)

Output:

Array: 
 [23, 45, 34, 78, 23, 78, 12, 89, 45, 34, 54, 34]


Array After Removing Duplicate:
 [23, 45, 34, 78, 12, 89, 54]

 

03. Method: Using Dictionary.

01. Example

Apply on string list.

cars = ['Lamborghini','Honda', 'Jeep', 'Honda', 'BMW','Hyundai', 'Hyundai', 'BMW', 'Ford']
print("Array: n", cars)

result = list(dict.fromkeys(cars))
print("nnArray After Removing Duplicate:n",result)

Output:

Array: 
 ['Lamborghini', 'Honda', 'Jeep', 'Honda', 'BMW', 'Hyundai', 'Hyundai', 'BMW', 'Ford']


Array After Removing Duplicate:
 ['Lamborghini', 'Honda', 'Jeep', 'BMW', 'Hyundai', 'Ford']

 

02. Example

Apply on numeric list.

numbers = [23, 45, 34, 78, 23, 78, 12, 89, 45, 34, 54, 34]
print("Array: n", numbers)

result = list(dict.fromkeys(numbers))
print("nnArray After Removing Duplicate:n",result)

Output:

Array: 
 [23, 45, 34, 78, 23, 78, 12, 89, 45, 34, 54, 34]


Array After Removing Duplicate:
 [23, 45, 34, 78, 12, 89, 54]

 

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