Binary Indexed Tree LeetCode Problems: 32 Python Solutions

Binary Indexed Tree problems by difficulty

Problems with a complete Python solution are listed first, then by ascending problem number.

Medium (10)

Medium problems
No.	Problem	Topics
0307	Range Sum Query - Mutable	Design, Binary Indexed Tree, Segment Tree +2
0406	Queue Reconstruction by Height	Binary Indexed Tree, Segment Tree, Array +1
0673	Number of Longest Increasing Subsequence	Binary Indexed Tree, Segment Tree, Array +1
1395	Count Number of Teams	Binary Indexed Tree, Segment Tree, Array +1
1409	Queries on a Permutation With Key	Binary Indexed Tree, Array, Simulation
2250	Count Number of Rectangles Containing Each Point	Binary Indexed Tree, Array, Hash Table +2
2424	Longest Uploaded Prefix	Union Find, Design, Binary Indexed Tree +5
0308	Range Sum Query 2D - MutablePremium	Design, Binary Indexed Tree, Segment Tree +2
2031	Count Subarrays With More Ones Than ZerosPremium	Binary Indexed Tree, Segment Tree, Array +5
2907	Maximum Profitable Triplets With Increasing Prices IPremium	Binary Indexed Tree, Segment Tree, Array

Hard (22)

Hard problems
No.	Problem	Topics
0218	The Skyline Problem	Binary Indexed Tree, Segment Tree, Array +5
0315	Count of Smaller Numbers After Self	Binary Indexed Tree, Segment Tree, Array +4
0327	Count of Range Sum	Binary Indexed Tree, Segment Tree, Array +4
0493	Reverse Pairs	Binary Indexed Tree, Segment Tree, Array +4
1157	Online Majority Element In Subarray	Design, Binary Indexed Tree, Segment Tree +2
1505	Minimum Possible Integer After at Most K Adjacent Swaps On Digits	Greedy, Binary Indexed Tree, Segment Tree +1
1649	Create Sorted Array through Instructions	Binary Indexed Tree, Segment Tree, Array +4
1964	Find the Longest Valid Obstacle Course at Each Position	Binary Indexed Tree, Array, Binary Search
2179	Count Good Triplets in an Array	Binary Indexed Tree, Segment Tree, Array +4
2193	Minimum Number of Moves to Make Palindrome	Greedy, Binary Indexed Tree, Two Pointers +1
2286	Booking Concert Tickets in Groups	Design, Binary Indexed Tree, Segment Tree +1
2407	Longest Increasing Subsequence II	Binary Indexed Tree, Segment Tree, Queue +4
2426	Number of Pairs Satisfying Inequality	Binary Indexed Tree, Segment Tree, Array +4
2552	Count Increasing Quadruplets	Binary Indexed Tree, Array, Dynamic Programming +2
2659	Make Array Empty	Greedy, Binary Indexed Tree, Segment Tree +4
2736	Maximum Sum Queries	Stack, Binary Indexed Tree, Segment Tree +4
2926	Maximum Balanced Subsequence Sum	Binary Indexed Tree, Segment Tree, Array +2
2940	Find Building Where Alice and Bob Can Meet	Stack, Binary Indexed Tree, Segment Tree +4
0683	K Empty SlotsPremium	Binary Indexed Tree, Segment Tree, Queue +5
2519	Count the Number of K-Big IndicesPremium	Binary Indexed Tree, Segment Tree, Array +4
2916	Subarrays Distinct Element Sum of Squares II	Binary Indexed Tree, Segment Tree, Array +1
2921	Maximum Profitable Triplets With Increasing Prices IIPremium	Binary Indexed Tree, Segment Tree, Array

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python

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

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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GPT-6.1 Terra

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python

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

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.

Type your message...

GPT-6.1 TerraClear chat

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.

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.

Type your message...

GPT-6.1 TerraClear chat

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

Binary Indexed Tree LeetCode Problems: All 32,
With Python Solutions

Binary Indexed Tree problems by difficulty

Medium (10)

Hard (22)

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Binary Indexed Tree problems by difficulty

Medium (10)10

Hard (22)22

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Medium (10)

Hard (22)