Skip to content
Open
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
20 changes: 20 additions & 0 deletions Problem_1.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,20 @@
# https://www.geeksforgeeks.org/dsa/find-the-missing-number-in-a-sorted-array/
# https://leetcode.com/problems/missing-element-in-sorted-array/description/

# Time complexity: O(log n)
# Space complexity: O(1)
# Explanation: Use binary search to find where the difference between two indices changes from 1 to greater than 1 - that's where the number is missing

class Solution:
def missingElement(self, nums: List[int], k: int) -> int:
n = len(nums)
left, right = 0, n - 1

while left < right:
mid = right - (right - left) // 2
if (nums[mid] - nums[0]) - mid < k:
left = mid
else:
right = mid - 1

return nums[0] + k + left
65 changes: 65 additions & 0 deletions Problem_2.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,65 @@
# https://www.geeksforgeeks.org/dsa/introduction-to-min-heap-data-structure/

class MinHeap:
def __init__(self):
self.heap = []

# O(1)
def getMin(self):
if not self.heap:
return None
return self.heap[0]

# O(log n)
def insert(self, value):
# 1. Add to end
self.heap.append(value)

# 2. Bubble up
i = len(self.heap) - 1

while i > 0:
parent = (i - 1) // 2

if self.heap[parent] <= self.heap[i]:
break

self.heap[parent], self.heap[i] = self.heap[i], self.heap[parent]
i = parent

# O(log n)
def extractMin(self):
if not self.heap:
return None

# Only one element
if len(self.heap) == 1:
return self.heap.pop()

minimum = self.heap[0]

# Move last element to root
self.heap[0] = self.heap.pop()

# Bubble down
i = 0

while True:
left = 2 * i + 1
right = 2 * i + 2
smallest = i

if left < len(self.heap) and self.heap[left] < self.heap[smallest]:
smallest = left

if right < len(self.heap) and self.heap[right] < self.heap[smallest]:
smallest = right

# Heap property satisfied
if smallest == i:
break

self.heap[i], self.heap[smallest] = self.heap[smallest], self.heap[i]
i = smallest

return minimum