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Python: Check if there are duplicate values in a given flat list

Python List: Exercise - 271 with Solution

Write a Python program to check if there are duplicate values in a given flat list.

Use set() on the given list to remove duplicates, compare its length with the length of the list.

Sample Solution:

Python Code:

def has_duplicates(lst):
  return len(lst) != len(set(lst))
nums = [1, 2, 3, 4, 5, 6, 7]
print("Original list:")
print(nums)
print("Check if there are duplicate values in the said given flat list:")
print(has_duplicates(nums)) 
nums = [1, 2, 3, 3, 4, 5, 5, 6, 7]
print("\nOriginal list:")
print(nums)
print("Check if there are duplicate values in the said given flat list:")
print(has_duplicates(nums)) 

Sample Output:

Original list:
[1, 2, 3, 4, 5, 6, 7]
Check if there are duplicate values in the said given flat list:
False

Original list:
[1, 2, 3, 3, 4, 5, 5, 6, 7]
Check if there are duplicate values in the said given flat list:
True

Flowchart:

Flowchart: Check if there are duplicate values in a given flat list.

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Python Code Editor:

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Previous: Write a Python program to check if the elements of the first list are contained in the second one regardless of order.
Next: Write a Python program to generate a list of numbers in the arithmetic progression starting with the given positive integer and up to the specified limit.

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Python: Tips of the Day

Floor Division:

When we speak of division we normally mean (/) float division operator, this will give a precise result in float format with decimals.

For a rounded integer result there is (//) floor division operator in Python. Floor division will only give integer results that are round numbers.

print(1000 // 300)
print(1000 / 300)

Output:

3
3.3333333333333335