How hard is LeetCode 2634. Filter Elements from Array?

LeetCode 2634. Filter Elements from Array is rated Easy on LeetCode.

What is the time complexity of LeetCode 2634. Filter Elements from Array?

The Python solution on this page runs in O(n), where n is the length of the array arr.

What is the space complexity of LeetCode 2634. Filter Elements from Array?

The Python solution on this page uses O(1) auxiliary space.

What topics does LeetCode 2634. Filter Elements from Array cover?

LeetCode 2634. Filter Elements from Array is tagged JavaScript on LeetCode.

EasyNo. 2634

Filter Elements from Array — LeetCode 2634 Python Solution

Topics: JavaScript
Reading time: 2 min
Source: leetcode.com

The problem

Given an integer array arr and a filtering function fn, return a filtered array filteredArr. The fn function takes one or two arguments: arr[i] - number from the arr i - index of arr[i] filteredArr should only contain the elements from the arr for which the expression fn(arr[i], i) evaluates to a truthy value.

Example

Input: arr = [0,10,20,30], fn = function greaterThan10(n) { return n > 10; }
Output: [20,30]
Explanation: const newArray = filter(arr, fn); // [20, 30]

Complexity

Time: O(n)where n is the length of the array arr
Space · auxiliary: O(1)

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Frequently asked questions

How hard is LeetCode 2634. Filter Elements from Array?: LeetCode 2634. Filter Elements from Array is rated Easy on LeetCode.
What is the time complexity of LeetCode 2634. Filter Elements from Array?: The Python solution on this page runs in O(n), where n is the length of the array arr.
What is the space complexity of LeetCode 2634. Filter Elements from Array?: The Python solution on this page uses O(1) auxiliary space.
What topics does LeetCode 2634. Filter Elements from Array cover?: LeetCode 2634. Filter Elements from Array is tagged JavaScript on LeetCode.

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python

Please analyze this context and help me answer the question or solve the problem.

Transcript

"Okay, next one. Given a string, return the length of the longest substring that has no repeating characters. Walk me through your approach before you code it."

Technical interview · 45 minsolution.pyShared editor · Python 3Longest substring without repeatsMediumGiven a string s, return the length of the longest contiguous substring in which every character is unique.s = "abcabcbb"
→ 31def length_of_longest_substring(s: str) -> int:2 last_seen = {}3 left = best = 04 for right, ch in enumerate(s):5 if ch in last_seen and last_seen[ch] >= left:

python

def length_of_longest_substring(s: str) -> int:    last_seen = {}                    # char -> index    left = best = 0    for right, ch in enumerate(s):        if ch in last_seen and last_seen[ch] >= left:            left = last_seen[ch] + 1  # jump past it        last_seen[ch] = right        best = max(best, right - left + 1)    return best    last_seen = {}                    # char -> index

Approach

At each index r, the window's left edge is:

left r = max (left r -1, last[s r] + 1)

Time O(n): each character enters and leaves the window once.
Space O(min(n, k)): k is the size of the character set.

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Transcribing...

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python

Please analyze this context and help me answer the question or solve the problem.

Transcript

"Okay, next one. Given a string, return the length of the longest substring that has no repeating characters. Walk me through your approach before you code it."

python

def length_of_longest_substring(s: str) -> int:    last_seen = {}                    # char -> index    left = best = 0    for right, ch in enumerate(s):        if ch in last_seen and last_seen[ch] >= left:            left = last_seen[ch] + 1  # jump past it        last_seen[ch] = right        best = max(best, right - left + 1)    return best    last_seen = {}                    # char -> index

Approach

At each index r, the window's left edge is:

left r = max (left r -1, last[s r] + 1)

Time O(n): each character enters and leaves the window once.
Space O(min(n, k)): k is the size of the character set.

Type your message...

GPT-6.1 TerraClear chat

Transcribing...

QuitEscHide+QCapture+PCrop+OSubmit+EnterPress to get answerLeft/Right+Up/Down+

90%Subscription

python

Please analyze this context and help me answer the question or solve the problem.

Transcript

"Okay, next one. Given a string, return the length of the longest substring that has no repeating characters. Walk me through your approach before you code it."

python

def length_of_longest_substring(s: str) -> int:    last_seen = {}                    # char -> index    left = best = 0    for right, ch in enumerate(s):        if ch in last_seen and last_seen[ch] >= left:            left = last_seen[ch] + 1  # jump past it        last_seen[ch] = right        best = max(best, right - left + 1)    return best    last_seen = {}                    # char -> index

Approach

At each index r, the window's left edge is:

left r = max (left r -1, last[s r] + 1)

Time O(n): each character enters and leaves the window once.
Space O(min(n, k)): k is the size of the character set.

Type your message...

GPT-6.1 TerraClear chat

Transcribing...

Primary display

QuitEscHide+QCapture+PCrop+OSubmit+EnterPress to get answerLeft/Right+Up/Down+

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