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# Python – Consecutive Ranges of K greater than N

Given a list of elements, the task is to write a Python program to get all ranges of K greater than N.

Input : [2, 6, 6, 6, 6, 5, 4, 6, 6, 8, 4, 6, 6, 6, 2, 6], K = 6, N = 3

Output : [(1, 4), (11, 13)]

Explanation : 6 is consecutive from index 1 to 4, hence 1-4 in result. 7-8 also has 6, but its less than 3 size range, hence not included in result.

Input : [2, 1, 1, 1, 1, 5, 4, 1, 1], K = 1, N = 3

Output : [(1, 4)]

Explanation : 1 is consecutive from index 1 to 4, hence 1-4 in result. 7-8 also has 1, but its less than 3 size range, hence not included in result.

Method #1: Using loop

In this, each occurrence of K is traced and a nested loop is employed to get the size of the range. If the range size is greater than N, the range is recorded in the result.

## Python3

 `# Python3 code to demonstrate working of``# Consecutive Ranges of K greater than N``# Using loop` `# initializing list``test_list ``=` `[``2``, ``6``, ``6``, ``6``, ``6``, ``5``, ``4``, ``6``,``             ``6``, ``8``, ``4``, ``6``, ``6``, ``6``, ``2``, ``6``]` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))` `# initializing K``K ``=` `6` `# initializing N``N ``=` `3` `res ``=` `[]``strt, end ``=` `0``, ``0``prev ``=` `1``for` `idx, ele ``in` `enumerate``(test_list):` `    ``# if ele K assign end``    ``if` `ele ``=``=` `K:``        ``end ``=` `idx` `        ``# if prev ele not K, reassign start``        ``if` `prev !``=` `K:     ``# previous item one``            ``strt ``=` `idx``    ``else``:` `        ``# if range is greater than N, append to result``        ``if` `prev ``=``=` `K ``and` `end ``-` `strt ``+` `1` `>``=` `N:``            ``res.append((strt, end))``    ``prev ``=` `ele` `# printing result``print``(``"The extracted ranges : "` `+` `str``(res))`

Output:

The original list is : [2, 6, 6, 6, 6, 5, 4, 6, 6, 8, 4, 6, 6, 6, 2, 6]

The extracted ranges : [(1, 4), (11, 13)]

Time Complexity: O(n)
Auxiliary Space: O(n)

Method #2 : Using enumerate() + zip() + list slicing + list comprehension

In this, all the pairs of ending and starting of K are extracted with previous and next element respectively. The pairs index are then checked to have required ranges in between to add to the result in the list.

## Python3

 `# Python3 code to demonstrate working of``# Consecutive Ranges of K greater than N``# Using enumerate() + zip() + list slice + list comprehension` `# initializing list``test_list ``=` `[``2``, ``6``, ``6``, ``6``, ``6``, ``5``, ``4``, ``6``,``             ``6``, ``8``, ``4``, ``6``, ``6``, ``6``, ``2``, ``6``]` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))` `# initializing K``K ``=` `6` `# initializing N``N ``=` `3` `# getting break pairs indices``brk_pairs ``=` `[idx ``for` `idx, (x, y) ``in` `enumerate``(``    ``zip``(test_list, test_list[``1``:]),``  ``1``) ``if` `(x ``=``=` `K) !``=` `(y ``=``=` `K)]` `# The ranges are checked for size required``res ``=` `[(idx, ele ``-` `1``) ``for` `idx, ele ``in` `zip``([K] ``+` `brk_pairs,``                                          ``brk_pairs ``+` `[``len``(test_list)])``       ``if` `ele ``-` `idx >``=` `N ``and` `test_list[idx] ``=``=` `K]` `# printing result``print``(``"The extracted ranges : "` `+` `str``(res))`

Output:

The original list is : [2, 6, 6, 6, 6, 5, 4, 6, 6, 8, 4, 6, 6, 6, 2, 6]

The extracted ranges : [(1, 4), (11, 13)]

Time complexity: O(n*n), where n is the length of the test_list. The enumerate() + zip() + list slicing + list comprehension takes O(n*n) time
Auxiliary Space: O(n), extra space of size n is required

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