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Algorithms & data structures

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2 matches
Algorithms & data structures medium

How to Find Intersection of Two Sorted Interval Lists in Python

A two-pointer algorithm that finds all overlapping intervals between two sorted lists of intervals.

intervals two-pointers algorithm
Python
def interval_intersection(list1, list2):
    i = j = 0
    result = []
    
    while i < len(list1) and j < len(list2):
        # Find the overlap between current intervals
        lo = max(list1[i][0], list2[j][0])
        hi = min(list1[i][1], list2[j][1])
        
        # If there's an overlap, add it to result
…
13 0 Open
Algorithms & data structures medium

Merge k sorted lists in Python using a heap

Merge k individually sorted lists into one sorted list in Python using a min-heap.

heapq merge sorted-list
Python
import heapq

def merge_k_sorted_lists(lists):
    heap = []
    # Push the first element of each list onto the heap
    for i, lst in enumerate(lists):
        if lst:
            heapq.heappush(heap, (lst[0], i, 0))
    
    result = []
    while heap:
        val, list_idx, elem_idx = heapq.heappop(heap)
        re…
15 0 Open

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