This is the master index for my series of Leetcode solution explanations. If you like these solutions or found them useful, please like this post.

### Hard Problem Solutions:

# |
TITLE |
RELATED TOPICS |
---|---|---|

32 | Longest Valid Parentheses | Stack |

51 | N-Queens | Backtracking, DFS, Recursion, Bit Manipulation |

52 | N-Queens II | Backtracking, DFS, Recursion, Bit Manipulation |

65 | Valid Number | String |

164 | Maximum Gap | Bucket Sort, Math |

329 | Longest Increasing Path in a Matrix | Recursion, DFS, Memoization |

336 | Palindrome Pairs | Map |

354 | Russian Doll Envelopes | LIS, Binary Search, DP |

630 | Course Schedule III | Priority Queue, Heap |

745 | Prefix and Suffix Search | Trie |

778 | Swim in Rising Water | Dijkstra's, Priority Queue, Heap |

871 | Minimum Number of Refueling Stops | Max Priority Queue, Max Heap, Greedy |

895 | Maximum Frequency Stack | Frequency Map, Stack |

906 | Super Palindromes | Math, Palindromes |

936 | Stamping The Sequence | Character Mask |

968 | Binary Tree Cameras | DFS, Recursion |

987 | Vertical Order Traversal of a Binary Tree | Tree, DFS, Recursion, Bit Manipulation |

1074 | Number of Submatrices That Sum to Target | Matrix, Map |

1192 | Critical Connections in a Network | Tarjan's |

1354 | Construct Target Array With Multiple Sums | Priority Queue, Heap |

1383 | Maximum Performance of a Team | Priority Queue, Heap |

1713 | Minimum Operations to Make a Subsequence | LCS, LIS, Binary Search |

1735 | Count Ways to Make Array With Product | Math |

1739 | Building Boxes | Math |

## Discussion (2)

Pretty cool Sean. I'll definitely keep eyes on this series.

Actually, I'll make it better. I'll study one of them a day.

Thanks!

You're welcome, Rafael!

I've been doing the daily leetcode challenge problem pretty much every day for the past 8 months, and I will definitely agree that a little bit each day really helps!