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Python | Check if any element occurs n times in given list
• Last Updated : 08 Sep, 2020

Given a list, the task is to find whether any element occurs ‘n’ times in given list of integers. It will basically check for the first element that occurs n number of times.
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 do the task in Python –
Method 1: Using Simple Iteration and Sort

## Python3

 `# Python code to find occurrence of any element``# appearing 'n' times` `# Input Initialisation``input` `=` `[``1``, ``2``, ``3``, ``0``, ``4``, ``3``, ``4``, ``0``, ``0``]` `# Sort Input``input``.sort()` `# Constants 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 no element is 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 Count

## Python3

 `# Python code to find occurrence of any element``# appearing 'n' times` `# Input list initialisation``input` `=` `[``1``, ``2``, ``3``, ``4``, ``0``, ``4``, ``3``, ``4``]` `# Constant declaration``n ``=` `3` `# print``print``(``"There are {} occurrences of {} in {}"``.``format``(``input``.count(n), n, ``input``))`

Output :

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

```

Method 3: Using defaultdict
We first populate item of list in a dictionary and then we find whether count of any element is equal to n.

## Python3

 `# Python code to find occurrence of any element``# appearing 'n' times` `# importing``from` `collections ``import` `defaultdict` `# Dictionary declaration``dic ``=` `defaultdict(``int``)` `# Input list initialisation``Input` `=` `[``9``, ``8``, ``7``, ``6``, ``5``, ``9``, ``2``]` `# Dictionary populate``for` `i ``in` `Input``:``    ``dic[i]``+``=` `1` `# constant declaration``n ``=` `2``flag ``=` `0` `# Finding from dictionary``for` `element ``in` `Input``:``    ``if` `element ``in` `dic.keys() ``and` `dic[element] ``=``=` `n:``        ``print``(``"Yes, {} has {} occurrence in {}."``.``format``(element, n, ``Input``))``        ``flag ``=` `1``        ``break` `# if element 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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