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4,005 problems

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Array2,209 String870 Hash Table786 Math682 Dynamic Programming666 Sorting504 Greedy480 Binary Search352 Depth-First Search335 Database303 Bit Manipulation283 Matrix278 Tree261 Breadth-First Search255 Two Pointers249 All topics

With video · 4,005 results

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TitleSolutionAcceptDifficultyTopics

101. Symmetric TreeVideo

Solution62.1%Easy

Binary Tree, Breadth-First Search +2· 11 companies

102. Binary Tree Level Order TraversalVideo

Solution73.5%Medium

Binary Tree, Breadth-First Search +1· 16 companies

103. Binary Tree Zigzag Level Order TraversalVideo

Solution64.4%Medium

Binary Tree, Breadth-First Search +1· 19 companies

104. Maximum Depth of Binary TreeVideo

Solution78.6%Easy

Binary Tree, Breadth-First Search +2· 17 companies

105. Construct Binary Tree from Preorder and Inorder TraversalVideo

Solution69.7%Medium

Array, Binary Tree +3· 9 companies

106. Construct Binary Tree from Inorder and Postorder TraversalVideo

Solution69.4%Medium

Array, Binary Tree +3· 7 companies

107. Binary Tree Level Order Traversal IIVideo

Solution69.0%Medium

Binary Tree, Breadth-First Search +1· 6 companies

108. Convert Sorted Array to Binary Search TreeVideo

Solution75.9%Easy

Array, Binary Search Tree +3· 9 companies

109. Convert Sorted List to Binary Search TreeVideo

Solution67.4%Medium

Binary Search Tree, Binary Tree +3· 9 companies

110. Balanced Binary TreeVideo

Solution59.2%Easy

Binary Tree, Depth-First Search +1· 9 companies

111. Minimum Depth of Binary TreeVideo

Solution53.7%Easy

Binary Tree, Breadth-First Search +2· 7 companies

112. Path SumVideo

Solution55.8%Easy

Binary Tree, Breadth-First Search +2· 9 companies

113. Path Sum IIVideo

Solution62.6%Medium

Backtracking, Binary Tree +2· 10 companies

114. Flatten Binary Tree to Linked ListVideo

Solution71.6%Medium

Binary Tree, Depth-First Search +3· 8 companies

115. Distinct SubsequencesVideo

Solution54.1%Hard

Dynamic Programming, String· 13 companies

116. Populating Next Right Pointers in Each NodeVideo

Solution67.6%Medium

Binary Tree, Breadth-First Search +3· 8 companies

117. Populating Next Right Pointers in Each Node IIVideo

Solution57.9%Medium

Binary Tree, Breadth-First Search +3· 7 companies

118. Pascal's TriangleVideo

Solution79.4%Easy

Array, Dynamic Programming· 17 companies

119. Pascal's Triangle IIVideo

Solution67.8%Easy

Array, Dynamic Programming· 6 companies

120. TriangleVideo

Solution59.9%Medium

Array, Dynamic Programming· 11 companies

121. Best Time to Buy and Sell StockVideo

Solution57.1%Easy

Array, Dynamic Programming· 92 companies

122. Best Time to Buy and Sell Stock IIVideo

Solution71.4%Medium

Array, Dynamic Programming +1· 28 companies

123. Best Time to Buy and Sell Stock IIIVideo

Solution54.5%Hard

Array, Dynamic Programming· 13 companies

124. Binary Tree Maximum Path SumVideo

Solution42.7%Hard

Binary Tree, Depth-First Search +2· 25 companies

125. Valid PalindromeVideo

Solution54.2%Easy

String, Two Pointers· 39 companies

126. Word Ladder IIVideo

Solution27.7%Hard

Backtracking, Breadth-First Search +2· 15 companies

127. Word LadderVideo

Solution46.3%Hard

Breadth-First Search, Hash Table +1· 41 companies

128. Longest Consecutive SequenceVideo

Solution47.0%Medium

Array, Hash Table +1· 40 companies

129. Sum Root to Leaf NumbersVideo

Solution70.3%Medium

Binary Tree, Depth-First Search +1· 7 companies

130. Surrounded RegionsVideo

Solution46.1%Medium

Array, Breadth-First Search +3· 12 companies

131. Palindrome PartitioningVideo

Solution74.4%Medium

Backtracking, Dynamic Programming +1· 10 companies

132. Palindrome Partitioning IIVideo

Solution37.9%Hard

Dynamic Programming, String· 9 companies

133. Clone GraphVideo

Solution66.1%Medium

Breadth-First Search, Depth-First Search +2· 18 companies

134. Gas StationVideo

Solution48.4%Medium

Array, Greedy· 29 companies

135. CandyVideo

Solution49.3%Hard

Array, Greedy· 24 companies

136. Single NumberVideo

Solution78.1%Easy

Array, Bit Manipulation· 15 companies

137. Single Number IIVideo

Solution68.0%Medium

Array, Bit Manipulation· 5 companies

138. Copy List with Random PointerVideo

Solution63.8%Medium

Hash Table, Linked List· 22 companies

139. Word BreakVideo

Solution49.8%Medium

Array, Dynamic Programming +4· 32 companies

140. Word Break IIVideo

Solution56.4%Hard

Array, Backtracking +5· 16 companies

141. Linked List CycleVideo

Solution55.2%Easy

Hash Table, Linked List +1· 24 companies

142. Linked List Cycle IIVideo

Solution59.3%Medium

Hash Table, Linked List +1· 13 companies

143. Reorder ListVideo

Solution66.0%Medium

Linked List, Recursion +2· 15 companies

144. Binary Tree Preorder TraversalVideo

Solution76.6%Easy

Binary Tree, Depth-First Search +2· 5 companies

145. Binary Tree Postorder TraversalVideo

Solution79.0%Easy

Binary Tree, Depth-First Search +2· 5 companies

146. LRU CacheVideo

Solution48.2%Medium

Design, Doubly-Linked List +2· 120 companies

147. Insertion Sort ListVideo

Solution60.5%Medium

Linked List, Sorting· 5 companies

148. Sort ListVideo

Solution65.2%Medium

Divide and Conquer, Linked List +3· 9 companies

149. Max Points on a LineVideo

Solution31.6%Hard

Array, Geometry +2· 16 companies

150. Evaluate Reverse Polish NotationVideo

Solution58.5%Medium

Array, Math +1· 18 companies

Showing 101–150 of 4,005