547. 20541 2321 Add to List Share. LeetCode is hiring! Apply NOW. Submissions. Hard #24 Swap Nodes in Pairs. WebGiven two strings s and t, return true if s is a subsequence of t, or false otherwise.. A subsequence of a string is a new string that is formed from the original string by deleting some (can be none) of the characters without disturbing the relative positions of the remaining characters. Medium. Matrix Block Sum. #21 Merge Two Sorted Lists. Hard #24 Swap Nodes in Pairs. You may assume the two numbers do not contain any leading zero, except the number 0 itself. Hard. Hard #24 Swap Nodes in Pairs. Discuss (365) Submissions. Hook hookhook:jsv8jseval Hard #5 Longest Palindromic Substring. New. Median of Two Sorted Arrays. 1995. WebYou are given two non-empty linked lists representing two non-negative integers. ketong 178. 1195. WebSolution. 18. Space complexity: O (1) O(1) O (1) We count the majority of each bit in O (1) O(1) O (1) space as it only has the two potential values, 0 and 1. Medium #7 Reverse Integer. New. WebA string s is nice if, for every letter of the alphabet that s contains, it appears both in uppercase and lowercase. WebWithout a Kleene star, our solution would look like this: If a star is present in the pattern, it will be in the second position e x t p a t t e r n [ 1 ] ext{pattern[1]} e x t p a t t e r n [ 1 ] . WebSolution. You may assume the two numbers do not contain any leading zero, except the number 0 itself. C++ || SOLUTION. Medium #7 Reverse Integer. 2. Medium #23 Merge k Sorted Lists. Example 1: Letter Combinations of a Phone Number. Apply NOW. #4 Median of Two Sorted Arrays. Given two sorted arrays nums1 and nums2 of size m and n respectively, return the median of the two sorted arrays. The numerical value of some string of lowercase English letters s is the concatenation of the letter values of each letter in s, which is then converted into an integer.. For example, if s = "acb", we concatenate each letter's letter value, resulting in "021". For example, "abABB" is nice because 'A' and 'a' appear, and 'B' and 'b' appear. WebGiven two strings s and t of lengths m and n respectively, return the minimum window substring of s such that every character in t (including duplicates) is included in the window.If there is no such substring, return the empty string "".. C++ || SOLUTION. WebSolution. Easy #22 Generate Parentheses. Median of two sorted arrays in Break a Palindrome #4 Median of Two Sorted Arrays. Easy #22 Generate Parentheses. 121. Hot Newest to Oldest Most Votes. Medium #23 Merge k Sorted Lists. #21 Merge Two Sorted Lists. Given a string s, return the longest substring of s that is nice.If there are multiple, return the substring of We enumerate all log C \log{C} lo g C bits for each number in nums. Show 46 replies. Apply NOW. Submissions. Medium #7 Reverse Integer. To solve the problem, let's look at the condition carefully, It is guaranteed that the given array is a sorted array.. Let k be the count of unique elements in our input array.. Hard #24 Swap Nodes in Pairs. It doesn't matter what elements we place after the first k elements.. From the condition, we can have a few observations here, New. Medium #7 Reverse Integer. Follow up: The overall run time complexity should Hard #24 6352 269 Add to List Share. 2. #4 Median of Two Sorted Arrays. Linear data structure: Data structure in which data elements are arranged sequentially or linearly, where each element is attached to its previous and next adjacent elements, is called a linear data structure. Easy #22 Generate Parentheses. WebSolution. Hard #5 Longest Palindromic Substring. Hard #5 Longest Palindromic Substring. For example, to compress the string "aabccc" we replace "aa" by "a2" and replace "ccc" by "c3".Thus the C Solution with Clean Code O((M+N)/2) c c code. New. vitrano created at: a day ago | Last Reply: Ejh2998 a day ago. Hard #24 Swap Nodes in Pairs. binary-search c++ cpp + 2 more. LeetCode is hiring! Hard #24 Swap Nodes in Pairs. Hard #5 Longest Palindromic Substring. Js20-Hook . Hot Newest to Oldest Most Votes. Easy #22 Generate Parentheses. C++ || SOLUTION. Discuss (999+) Submissions. WebRoman numerals are represented by seven different symbols: I, V, X, L, C, D and M. Symbol Value I 1 V 5 X 10 L 50 C 100 D 500 M 1000. C Solution with Clean Code O((M+N)/2) c c code. WebGiven two strings s and t, return true if s is a subsequence of t, or false otherwise.. A subsequence of a string is a new string that is formed from the original string by deleting some (can be none) of the characters without disturbing the relative positions of the remaining characters. WebLet's play the minesweeper game (Wikipedia, online game)!You are given an m x n char matrix board representing the game board where: 'M' represents an unrevealed mine, 'E' represents an unrevealed empty square, 'B' represents a revealed blank square that has no adjacent mines (i.e., above, below, left, right, and all 4 diagonals), digit ('1' to '8') Medium #23 Merge k Sorted Lists. 2. However, "abA" is not because 'b' appears, but 'B' does not. #21 Merge Two Sorted Lists. WebYou can never figure out a bottom-up DP solution without first figuring out a top down recursive approach. 4. Report. 4. Hard #24 Break a Palindrome #4 Median of Two Sorted Arrays. Medium #7 Reverse Integer. Medium #23 Merge k Sorted Lists. Easy #22 Generate Parentheses. How to view the solution in c. 1.1K. vitrano created at: a day ago | Last Reply: Ejh2998 a day ago. #21 Merge Two Sorted Lists. Hard #24 Swap Nodes in Pairs. Reply. Note that k is guaranteed to be a positive integer.. You may assume that the input string is always valid; there are no extra white spaces, square brackets are well-formed, etc. 4Sum. Share. Discuss (999+) Submissions. WebRun-length encoding is a string compression method that works by replacing consecutive identical characters (repeated 2 or more times) with the concatenation of the character and the number marking the count of the characters (length of the run). Given two sorted arrays nums1 and nums2 of size m and n respectively, return the median of the two sorted arrays. Medium #23 Merge k Sorted Lists. The level of a WebSolution. Hard #5 Longest Palindromic Substring. Hard #5 Longest Palindromic Substring. Approach 1: Two indexes approach Intuition. Hot Newest to Oldest Most Votes. 4. Medium #6 Zigzag Conversion. #4 Median of Two Sorted Arrays. Hard #24 Swap Nodes in Pairs. Hard #5 Longest Palindromic Substring. Example 1: Input: s = "bab", t = "aba" WebYou are given an m x n integer matrix points (0-indexed).Starting with 0 points, you want to maximize the number of points you can get from the matrix.. To gain points, you must pick one cell in each row.Picking the cell at coordinates (r, c) will add points[r][c] to your score.. The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is being repeated exactly k times. Hard #24 You should implement a data structure that can encrypt or decrypt a 0-indexed string.. A string is encrypted with the Hard #24 Swap Nodes in Pairs. Given two sorted arrays nums1 and nums2 of size m and n respectively, return the median of the two sorted arrays. #21 Merge Two Sorted Lists. Thank you for using LeetCode! The overall run time complexity should be O(log (m+n)). Medium. Medium. Discuss (365) Submissions. Medium #6 Zigzag Conversion. The frequency of a letter x is the number of times it occurs ; Return the root of the reversed tree.. A binary tree is perfect if all parent nodes have two children and all leaves are on the same level.. binary-search c++ cpp + 2 more. Medium. Following a bumpy launch week that saw frequent server trouble and bloated player queues, Blizzard has announced that over 25 million Overwatch 2 players have logged on in its first 10 days. WebYou can never figure out a bottom-up DP solution without first figuring out a top down recursive approach. Apply NOW. Submissions. Medium #23 Merge k Sorted Lists. 97. #4 Median of Two Sorted Arrays. Example 1: Input: s = "loveleetcode", c = "e" Output: vitrano created at: a day ago | Last Reply: Ejh2998 a day ago. WebYou are given two non-empty linked lists representing two non-negative integers. Medium #7 Reverse Integer. Share. If during the recursion you find you're solving the same sub-problem repeatedly ("overlapping sub-problems") - that's the first hint that its DP. Hard #24 Swap Nodes in Pairs. Medium #23 Merge k Sorted Lists. Easy #22 Generate Parentheses. Medium #6 Zigzag Conversion. Matrix Block Sum. Fizz Buzz Multithreaded. New. C Solution with Clean Code O((M+N)/2) c c code. Medium. Easy #22 Generate Parentheses. WebSolution. Static data structure: Static data structure has a fixed WebYou are given an m x n integer matrix points (0-indexed).Starting with 0 points, you want to maximize the number of points you can get from the matrix.. To gain points, you must pick one cell in each row.Picking the cell at coordinates (r, c) will add points[r][c] to your score.. 1314. WebSolution. Easy #22 Generate Parentheses. #21 Merge Two Sorted Lists. WebYou are given a character array keys containing unique characters and a string array values containing strings of length 2. Hard #5 Longest Palindromic Substring. Easy #22 Generate Parentheses. Medium #7 Reverse Integer. Hard #24 Swap Nodes in Pairs. Interleaving String. Medium #23 Merge k Sorted Lists. 18. Discuss (999+) Submissions. Medium #7 Reverse Integer. #4 Median of Two Sorted Arrays. Medium #6 Zigzag Conversion. Note that k is guaranteed to be a positive integer.. You may assume that the input string is always valid; there are no extra white spaces, square brackets are well-formed, etc. #4 Median of Two Sorted Arrays. Discuss (999+) Submissions. It doesn't matter what elements we place after the first k elements.. From the condition, we can have a few observations here, Hard #5 Longest Palindromic Substring. WebRoman numerals are represented by seven different symbols: I, V, X, L, C, D and M. Symbol Value I 1 V 5 X 10 L 50 C 100 D 500 M 1000. WebSolution. ; Return the root of the reversed tree.. A binary tree is perfect if all parent nodes have two children and all leaves are on the same level.. WebSolution. (i.e., "ace" is a subsequence of "abcde" while "aec" is not). 4. #4 Median of Two Sorted Arrays. Medium #21 Merge Two Sorted Lists. 18. #21 Merge Two Sorted Lists. Discuss (999+) Submissions. 4Sum. To view this solution, you must subscribe to premium. WebYou can never figure out a bottom-up DP solution without first figuring out a top down recursive approach. Medium #6 Zigzag Conversion. Count Special Quadruplets. Medium #7 Reverse Integer. Medium #23 Merge k Sorted Lists. Given a non-negative integer c, decide whether there're two integers a and b such that a 2 + b 2 = c. Example 1: Input: c = 5 Output: true Explanation: 1 * 1 + 2 * 2 = 5 Example 2: #4 Median of Two Sorted Arrays. Easy #22 Generate Parentheses. The distance between two indices i and j is abs(i - j), where abs is the absolute value function.. The digits are stored in reverse order, and each of their nodes contains a single digit. However, "abA" is not because 'b' appears, but 'B' does not. #21 Merge Two Sorted Lists. Hard #5 Longest Palindromic Substring. You are also given another string array dictionary that contains all permitted original strings after decryption. The frequency of a letter x is the number of times it occurs Medium #7 1791 494 Add to List Share. The distance between two indices i and j is abs(i - j), where abs is the absolute value function.. 2. Break a Palindrome #4 Median of Two Sorted Arrays. Hard #5 Longest Palindromic Substring. Example 1: Input: s = "loveleetcode", c = "e" Output: #4 Median of Two Sorted Arrays. Thank you for using LeetCode! "Sinc WebGiven two strings s and t of lengths m and n respectively, return the minimum window substring of s such that every character in t (including duplicates) is included in the window.If there is no such substring, return the empty string "".. Following a bumpy launch week that saw frequent server trouble and bloated player queues, Blizzard has announced that over 25 million Overwatch 2 players have logged on in its first 10 days. binary-search c++ cpp + 2 more. Discuss (365) Submissions. vitrano created at: a day ago | Last Reply: Ejh2998 a day ago. LeetCode is hiring! Then, we may ignore this part of the pattern, or delete a matching character in the text. Medium. Space complexity: O (1) O(1) O (1) We count the majority of each bit in O (1) O(1) O (1) space as it only has the two potential values, 0 and 1. WebSolution. 17. Apply NOW. Submissions. Medium #7 Reverse Integer. WebSolution. WebSolution. Medium #7 Reverse Integer. Discuss (214) Submissions. Hard. Medium #23 Merge k Sorted Lists. C Solution with Clean Code O((M+N)/2) c c code. Matrix Block Sum. Medium #23 Merge k Sorted Lists. For example, 2 is written as II in Roman numeral, just two one's added together.12 is written as XII, which is simply X + II.The number 27 is written as XXVII, which is XX + V + II. C C C is the max absolute value in nums, i.e., 1 0 5 10^5 1 0 5 in this problem. Hard #5 Longest Palindromic Substring. #4 Median of Two Sorted Arrays. Medium #23 Merge k Sorted Lists. Medium. Medium #7 Reverse Integer. Hard #5 Longest Palindromic Substring. WebA string s is nice if, for every letter of the alphabet that s contains, it appears both in uppercase and lowercase. C++ || SOLUTION. Medium #6 Zigzag Conversion. Medium #6 Zigzag Conversion. Hard #5 Longest Palindromic Substring. Hard #5 Longest Palindromic Substring. Hard #5 Longest Palindromic Substring. C++ || SOLUTION. Medium. #4 Median of Two Sorted Arrays. Medium #7 Reverse Integer. For example, to compress the string "aabccc" we replace "aa" by "a2" and replace "ccc" by "c3".Thus the You may assume the two numbers do not contain any leading zero, except the number 0 itself. How to view the solution in c. 1.1K. Easy. Apply NOW. Submissions. "Sinc Hard #5 Longest Palindromic Substring. Medium #7 Reverse Integer. Discuss (999+) Submissions. Median of Two Sorted Arrays. Number of Provinces. WebSolution. Medium. #4 Median of Two Sorted Arrays. 1328. binary-search c++ cpp + 2 more. Medium. 121. #4 Median of Two Sorted Arrays. WebSolution. C++ || SOLUTION. 4. 1195. For example, "abABB" is nice because 'A' and 'a' appear, and 'B' and 'b' appear. Thank you for using LeetCode! Medium #6 Zigzag Conversion. 121. #21 Merge Two Sorted Lists. Discuss (999+) Submissions. Medium #23 Merge k Sorted Lists. Add the two numbers and return the sum as a linked list. Medium #7 Reverse Integer. 0004 - Median Of Two Sorted Arrays. Today we are going to discuss a new LeetCode problem - Median Of Two Sorted Arrays. Hard #5 Longest Palindromic Substring. Medium #6 Zigzag Conversion. Easy #22 Generate Parentheses. The digits are stored in reverse order, and each of their nodes contains a single digit. WebSolution. Hard #5 Longest Palindromic Substring. The numerical value of some string of lowercase English letters s is the concatenation of the letter values of each letter in s, which is then converted into an integer.. For example, if s = "acb", we concatenate each letter's letter value, resulting in "021". New. Medium #7 Reverse Integer. #4 Median of Two Sorted Arrays. Apply NOW. Submissions. Median of two sorted arrays in Medium #23 Merge k Sorted Lists. #21 Merge Two Sorted Lists. #4 Median of Two Sorted Arrays. You should implement a data structure that can encrypt or decrypt a 0-indexed string.. A string is encrypted with the C Solution with Clean Code O((M+N)/2) c c code. Medium. Hard #24 Swap Nodes in Pairs. C Solution with Clean Code O((M+N)/2) c c code. Medium. Discuss (999+) Submissions. Medium #23 Merge k Sorted Lists. 0004 - Median Of Two Sorted Arrays. Hard #24 Swap Nodes in Pairs. #4 Median of Two Sorted Arrays. 4. Discuss (999+) Submissions. 1328. Number of Provinces. Discuss (999+) Submissions. Medium #23 Merge k Sorted Lists. Medium #7 Reverse Integer. Medium #23 Merge k Sorted Lists. Hot Newest to Oldest Most Votes. Medium #23 Merge k Sorted Lists. The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is being repeated exactly k times. Web LeetCode is hiring! Medium #6 Zigzag Conversion. Medium #23 Merge k Sorted Lists. Easy. Hard #5 Longest Palindromic Substring. 121. #21 Merge Two Sorted Lists. Medium #6 Zigzag Conversion. 6352 269 Add to List Share. 121. Easy #22 Generate Parentheses. Hard #5 Longest Palindromic Substring. Example 1: #4 Median of Two Sorted Arrays. WebGiven an encoded string, return its decoded string. Median of two sorted arrays in #4 Median of Two Sorted Arrays. Fizz Buzz Multithreaded. To solve the problem, let's look at the condition carefully, It is guaranteed that the given array is a sorted array.. Let k be the count of unique elements in our input array.. #21 Merge Two Sorted Lists. Example 1: Input: s = "loveleetcode", c = "e" Output: Median of Two Sorted Arrays. Today we are going to discuss a new LeetCode problem - Median Of Two Sorted Arrays. #21 Merge Two Sorted Lists. Easy #22 Generate Parentheses. 1995. Medium #7 Reverse Integer. Apply NOW. Submissions. 2. #4 Median of Two Sorted Arrays. Easy #22 Generate Parentheses. WebThe letter value of a letter is its position in the alphabet starting from 0 (i.e. LeetCode is hiring! WebSolution. WebSolution. Hard #5 Longest Palindromic Substring. Medium #7 Reverse Integer. The testcases will be generated such that the answer is unique.. A substring is a contiguous sequence of Hot Newest to Oldest Most Votes. 'a' -> 0, 'b' -> 1, 'c' -> 2, etc.).. Given a non-negative integer c, decide whether there're two integers a and b such that a 2 + b 2 = c. Example 1: Input: c = 5 Output: true Explanation: 1 * 1 + 2 * 2 = 5 Example 2: #4 Median of Two Sorted Arrays. ketong 178. 18. Subscribe Watch Preview Solution Article. Number of Provinces. 2. Then, we may ignore this part of the pattern, or delete a matching character in the text. #4 Median of Two Sorted Arrays. #4 Median of Two Sorted Arrays. Medium #7 Reverse Integer. Medium #6 Zigzag Conversion. The numerical value of some string of lowercase English letters s is the concatenation of the letter values of each letter in s, which is then converted into an integer.. For example, if s = "acb", we concatenate each letter's letter value, resulting in "021". Report. However, you will lose points if you pick a cell too far from the cell that you picked in the Note that k is guaranteed to be a positive integer.. You may assume that the input string is always valid; there are no extra white spaces, square brackets are well-formed, etc. binary-search c++ cpp + 2 more. Easy #22 Generate Parentheses. Medium #7 Reverse Integer. 18. Hard #5 Longest Palindromic Substring. WebRoman numerals are represented by seven different symbols: I, V, X, L, C, D and M. Symbol Value I 1 V 5 X 10 L 50 C 100 D 500 M 1000. Easy #22 Generate Parentheses. Discuss (999+) Submissions. For example, 2 is written as II in Roman numeral, just two ones added together.12 is written as XII, which is simply X + II.The number 27 is written as XXVII, which is XX + V + II. Medium #6 Zigzag Conversion. Medium #6 Zigzag Conversion. Median of Two Sorted Arrays. Whats up happy folks ! For example, 2 is written as II in Roman numeral, just two ones added together.12 is written as XII, which is simply X + II.The number 27 is written as XXVII, which is XX + V + II. (i.e., "ace" is a subsequence of "abcde" while "aec" is not). binary-search c++ cpp + 2 more. Example 1: Input: s = "bab", t = "aba" Medium. Given two sorted arrays nums1 and nums2 of size m and n respectively, return the median of the two sorted arrays. C++ || SOLUTION. For example, 2 is written as II in Roman numeral, just two ones added together.12 is written as XII, which is simply X + II.The number 27 is written as XXVII, which is XX + V + II. Discuss (999+) Submissions. Medium #23 Merge k Sorted Lists. Apply NOW. #4 Median of Two Sorted Arrays. Medium #7 Reverse Integer. C Solution with Clean Code O((M+N)/2) c c code. vitrano created at: a day ago | Last Reply: Ejh2998 a day ago. #21 Merge Two Sorted Lists. Medium. The level of a WebLet's play the minesweeper game (Wikipedia, online game)!You are given an m x n char matrix board representing the game board where: 'M' represents an unrevealed mine, 'E' represents an unrevealed empty square, 'B' represents a revealed blank square that has no adjacent mines (i.e., above, below, left, right, and all 4 diagonals), digit ('1' to '8') For example, 2 is written as II in Roman numeral, just two one's added together.12 is written as XII, which is simply X + II.The number 27 is written as XXVII, which is XX + V + II. Medium #23 Merge k Sorted Lists. Example 1: Input: s = "bab", t = "aba" Hard #5 Longest Palindromic Substring. Median of two sorted arrays in WebSolution. 18. Discuss (999+) Submissions. Hard #24 Swap Nodes in Pairs. Discuss (214) Submissions. WebSolution. WebGiven a string s and a character c that occurs in s, return an array of integers answer where answer.length == s.length and answer[i] is the distance from index i to the closest occurrence of character c in s.. You are also given another string array dictionary that contains all permitted original strings after decryption. C C C is the max absolute value in nums, i.e., 1 0 5 10^5 1 0 5 in this problem. Median of two sorted arrays in Medium #6 Zigzag Conversion. Median of Two Sorted Arrays. Hard #5 Longest Palindromic Substring. 20541 2321 Add to List Share. To view this solution, you must subscribe to premium. #4 Median of Two Sorted Arrays. Medium #7 Reverse Integer. WebSolution. For example, to compress the string "aabccc" we replace "aa" by "a2" and replace "ccc" by "c3".Thus the Hard #5 Longest Palindromic Substring. New. Median of Two Sorted Arrays. Hard #5 Longest Palindromic Substring. Medium. Medium #7 Median of two sorted arrays in Hard #24 Swap Nodes in Pairs. Whats up happy folks ! Interleaving String. 1195. The digits are stored in reverse order, and each of their nodes contains a single digit. Easy #22 Generate Parentheses. Medium. However, you will lose points if you pick a cell too far from the cell that you picked in the Medium #6 Zigzag Conversion. WebSolution. Hard #5 Longest Palindromic Substring. #21 Merge Two Sorted Lists. Apply NOW. #4 Median of Two Sorted Arrays. Medium. #21 Merge Two Sorted Lists. 633. LeetCode is hiring! WebWithout a Kleene star, our solution would look like this: If a star is present in the pattern, it will be in the second position e x t p a t t e r n [ 1 ] ext{pattern[1]} e x t p a t t e r n [ 1 ] . #4 Median of Two Sorted Arrays. Hard #5 Longest Palindromic Substring. vitrano created at: a day ago | Last Reply: Ejh2998 a day ago. Given a string s, return the longest substring of s that is nice.If there are multiple, return the substring of Given two strings word1 and word2, each of length n, return true if word1 and word2 are almost equivalent, or false otherwise.. Medium #6 Zigzag Conversion. Medium #7 Reverse Integer. Linear data structure: Data structure in which data elements are arranged sequentially or linearly, where each element is attached to its previous and next adjacent elements, is called a linear data structure. Web LeetCode is hiring! Problem Statement. How to view the solution in c. 1.1K. Given two sorted arrays nums1 and nums2 of size m and n respectively, return the median of the two sorted arrays. 2. The overall run time complexity should be O(log (m+n)). binary-search c++ cpp + 2 more. Examples of linear data structures are array, stack, queue, linked list, etc. Easy #22 Generate Parentheses. You should implement a data structure that can encrypt or decrypt a 0-indexed string.. A string is encrypted with the Interleaving String. Hard #5 Longest Palindromic Substring. Hot Newest to Oldest Most Votes. Medium #23 Merge k Sorted Lists. Median of two sorted arrays in Follow up: The overall run time complexity should Discuss (999+) Submissions. Medium #7 Reverse Integer. Discuss (999+) Submissions. Js20-Hook . #21 Merge Two Sorted Lists. Medium. C++ || SOLUTION. You are also given another string array dictionary that contains all permitted original strings after decryption. Hard #24 Swap Nodes in Pairs. WebGiven two strings s and t, return true if s is a subsequence of t, or false otherwise.. A subsequence of a string is a new string that is formed from the original string by deleting some (can be none) of the characters without disturbing the relative positions of the remaining characters. Then, we may ignore this part of the pattern, or delete a matching character in the text. Medium. 97. 121. Example 1: However, you will lose points if you pick a cell too far from the cell that you picked in the WebYou are given a character array keys containing unique characters and a string array values containing strings of length 2. 4. Hard #24 #21 Merge Two Sorted Lists. WebRun-length encoding is a string compression method that works by replacing consecutive identical characters (repeated 2 or more times) with the concatenation of the character and the number marking the count of the characters (length of the run). Medium. Medium #6 Zigzag Conversion. WebSolution. #21 Merge Two Sorted Lists. 2. vitrano created at: a day ago | Last Reply: Ejh2998 a day ago. Discuss (652) Submissions. Medium #6 Zigzag Conversion. If during the recursion you find you're solving the same sub-problem repeatedly ("overlapping sub-problems") - that's the first hint that its DP.