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# Python | Check if any element in the given list occurs n times

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Examples :

`  Input:  l = [1, 2, 3, 4, 0, 4, 3, 2, 1, 2 ], n = 3  Output:  2  Input:  l = [1, 2, 3, 4, 0, 4, 3, 2, 1, 2, 1, 1 ], n = 4  Output:  1 `

Below are some methods to accomplish a task in Python —

Method 1: using simple iterate and sort

 ` # Python code to find occurrences of any element ` ` # appears & # 39; n & # 39; times `   ` # Initialize input ` ` input ` ` = ` ` [` ` 1 ` `, ` ` 2 ` `, ` ` 3 ` `, ` ` 0 ` `, ` ` 4 ` `, ` ` 3 ` `, ` ` 4 ` `, ` ` 0 ` `, ` ` 0 ` `] `   ` # Sort input ` ` input ` `. sort () `   ` # Constant Declaration ` ` n ` ` = ` ` 3 ` ` prev ` ` = ` ` - ` ` 1 ` ` count ` ` = ` ` 0 ` ` flag ` ` = ` ` 0 `   ` # Iterating ` ` for ` ` item ` ` in ` ` input ` `: ` ` if ` ` item ` ` = ` ` = ` ` prev: ` ` count ` ` = ` ` count ` ` + ` ` 1 ` ` else ` `: ` ` count ` ` = ` ` 1 ` ` prev ` ` = ` ` item `   ` ` ` if ` ` count ` ` = ` ` = ` ` n: ` ` flag ` ` = ` ` 1 ` ` print ` ` (` ` "There are {} occurrences of {} in {}" ` `. ` ` format ` ` (n, item, ` ` input ` `)) ` ` break `   ` # If the element was not found. ` ` if ` ` flag ` ` = ` ` = ` ` 0 ` `: ` ` print ` ` (` ` "No occurrences found" ` `) `

Output:

` There are 3 occurrences of 0 in [0, 0, 0, 1, 2, 3, 3 , 4, 4] `

Method 2: using counter

 ` # Python code to find occurrences of any element ` ` # & # 39; n & # 39; times `   ` # Initialize the input list ` ` input ` ` = ` ` [` ` 1 ` `, ` ` 2 ` `, ` ` 3 ` `, ` ` 4 ` `, ` ` 0 ` `, ` ` 4 ` `, ` ` 3 ` `, ` ` 4 ` `] `   ` # Constant declaration ` ` n ` ` = ` ` 3 ` ` `  ` # Print ` ` print ` ` (` `" There are {} occurrences of {} in {} "` `. ` ` format ` ` (n, ` ` input ` `. count (n), ` ` input ` `)) `

Output:

` There are 3 occurrences of 2 in [1, 2, 3, 4, 0, 4, 3, 4] `

Method 3: using defaultdict

First, we fill the list item in the dictionary and then find if the number of elements is equal to any element n.

 ` # Python code to find occurrences of any element ` ` # appears & # 39; n & # 39; times `   ` # import ` ` from ` ` collections ` ` import ` ` defaultdict `   ` # Dictionary declaration ` ` dic ` ` = ` ` defaultdict (` ` int ` `) `   ` # Initialize the insertion list ` ` Input ` ` = ` ` [` ` 9 ` `, ` ` 8 ` `, ` ` 7 ` `, ` ` 6 ` `, ` ` 5 , 9 , 2 ] ``   # Fill in the dictionary for i in Input : dic [i] + = 1   # permanent announcement n = 2 flag = 0    # Find from dictionary `` for ` ` element ` ` in ` ` Input ` `: ` ` if ` ` element ` ` in ` ` dic.keys () ` ` and ` ` dic [element] ` ` = ` ` = ` ` 2 ` `: ` ` ` ` print ` ` (` ` "Yes, {} has {} occurrence in {}." ` `. ` ` format ` ` (element, n, ` ` Input ` `)) ` ` flag ` ` = ` ` 1 ` ` break `   ` # if the element was not found. ` ` if ` ` flag ` ` = ` ` = ` ` 0 ` `: ` ` print ` ` (` ` "No occurrences found" ` `) `

Output:

` Yes, 9 has 2 occurrence in [9, 8, 7, 6, 5, 9, 2] `

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