---

100DaysCodingChallenege

We will be solving at least one question daily for next 100 days

I will be solving atleast a coding problem daily from the following sites :-

1. Codeforces - **( pk01 - 1247)
2. Codechef - **(pkpawan123 - 1707)
3. Atcoder - **(pawankumarpk - 539)
4. Leetcode - **(pkpawan - 1585)
5. Hackerearth - **(pawanhero247 - 1550)
6. Hackerrank - **(pawanhero237 - 1829)
7. Topcoder - **(pkpawan - 776)

I am starting this challenge on Dec 1 2020 . My rating on the following sites are as follows we will check the change due to this challenge.

SUCCESSFULLY COMPLETED #(100 DAYS CODING CHALLENGE) -> With more than 320+ problems solved in 100 days -> aggregate +ve rating changes on competitive programming sites

New Ratings after 100 Days challenege :-

1. Codechef - **(pkpawan123 - 1805)
2. Atcoder - **(pawankumarpk - 632)
3. Leetcode - **(pkpawan - 1777)
4. Hackerearth - **(pawanhero247 - 1550)
5. Hackerrank - **(pawanhero237 - 1829)
6. Codeforces - **( pk01 - 1173)
7. Topcoder - **(pkpawan - 726)

Day 1

1. Maximum Depth of Binary Tree [ https://leetcode.com/problems/maximum-depth-of-binary-tree/ ]

Day 2

1. Div.64 [ https://codeforces.com/problemset/problem/887/A ]
2. Knapsack [ https://codeforces.com/contest/1446/problem/A ]

Day 3

1. Save Konoha [ https://www.codechef.com/problems/SAVKONO ]
2. Air conditioner [ https://codeforces.com/problemset/problem/1304/C ]
3. minimum distances [ https://www.hackerrank.com/challenges/minimum-distances/problem ]
4. increasing order search tree [ https://leetcode.com/problems/increasing-order-search-tree/description/ ]
5. swap nodes in pairs [ https://leetcode.com/problems/swap-nodes-in-pairs/ ]

Day 4

1. Vaccine production [ https://www.codechef.com/DEC20B/problems/VACCINE1 ]
2. Cancel the trains [ https://codeforces.com/problemset/problem/1453/A ]
3. Suffix operations [ https://codeforces.com/contest/1453/problem/B ]
4. Rotate image [ https://leetcode.com/problems/rotate-image/ ]
5. The kth factor of n [ https://leetcode.com/problems/the-kth-factor-of-n/ ]

Day 5

1. Redundant Redundancy [ https://atcoder.jp/contests/arc110/tasks/arc110_a ]
2. Positive prefixes [ https://www.codechef.com/DEC20B/problems/POSPREFS ]
3. non- great equations [ https://www.hackerearth.com/problem/approximate/gne-1043a924/description/ ]
4. can place flowers [ https://leetcode.com/problems/can-place-flowers/ ]
5. FakeReportData [ https://arena.topcoder.com/#/u/practiceCode/18428/154470/16665/2/335156 ]

Day 6

1. Goal Parser Interpretation [ https://leetcode.com/problems/goal-parser-interpretation/ ]
2. Max number of K- sum pairs [ https://leetcode.com/problems/max-number-of-k-sum-pairs/ ]
3. Concatenation of consecutive binary numbers [ https://leetcode.com/problems/concatenation-of-consecutive-binary-numbers/ ]
4. Populating Next Right Pointers in Each Node II [ https://leetcode.com/problems/populating-next-right-pointers-in-each-node-ii/ ]
5. Farmer and his plot [ https://www.codechef.com/problems/RECTSQ ]
6. Avoid trygub [ https://codeforces.com/contest/1450/problem/A ]
7. Balls of steel [ https://codeforces.com/contest/1450/problem/B ]

Day7

1. Spiral matrix II [ https://leetcode.com/problems/spiral-matrix-ii/ ]
2. Palindromic Substring [ https://leetcode.com/problems/palindromic-substrings/]
3. Longest Plaindromic subtring [ https://leetcode.com/problems/longest-palindromic-substring/]

Day8

1.Pairs of Songs With Total Durations Divisible by 60 [ https://leetcode.com/explore/challenge/card/december-leetcoding-challenge/570/week-2-december-8th-december-14th/3559/]

Day9

1. Hail Xor( HXOR) [ https://www.codechef.com/DEC20B/problems/HXOR ]
2. Equalize prizes [ https://codeforces.com/problemset/problem/1183/B ]

Day10

1. Valid Mountain Array [ https://leetcode.com/problems/valid-mountain-array/]
2. Petya and staircases [ https://codeforces.com/problemset/problem/362/B ]
3. Sherlock and XOR [ https://www.hackerearth.com/practice/basic-programming/bit-manipulation/basics-of-bit-manipulation/practice-problems/algorithm/sherlock-and-xor/submissions/ ]

Day11

1. Milly and string [ https://www.hackerearth.com/problem/algorithm/milly-and-strings/]
2. Remove dupliates from sorted array [ https://leetcode.com/problems/remove-duplicates-from-sorted-array-ii/]
3. String Generation [ https://codeforces.com/contest/1461/problem/A]
4. Is this a binary search tree ? [ https://www.hackerrank.com/challenges/is-binary-search-tree/problem ]

Day12

1. Binary Tree Inorder Traversal [ https://leetcode.com/problems/binary-tree-inorder-traversal/]
2. Binary Tree Postorder Traversal [ https://leetcode.com/problems/binary-tree-postorder-traversal/]
3. Count number of consistent string [ https://leetcode.com/problems/count-the-number-of-consistent-strings/ ]
4. Sum of Absolute Difference in a Sorted Array [ https://leetcode.com/problems/sum-of-absolute-differences-in-a-sorted-array/]
5. Stone Game VI [ https://leetcode.com/problems/stone-game-vi/ ]
6. Counting sort I [ https://www.hackerrank.com/challenges/countingsort1/problem ]

Day13

1. Count of matches in tournamnet [ https://leetcode.com/problems/count-of-matches-in-tournament/ ]
2. Partitioning into Minimum Number of Deci Binary numbers [ https://leetcode.com/problems/partitioning-into-minimum-number-of-deci-binary-numbers/]
3. ABC preparation [ https://atcoder.jp/contests/abc185/tasks/abc185_a]
4. Smartphone Addiction [ https://atcoder.jp/contests/abc185/tasks/abc185_b ]
5. Duodecim ferra [ https://atcoder.jp/contests/abc185/tasks/abc185_c ]
6. Stamp [ https://atcoder.jp/contests/abc185/tasks/abc185_d]

Day14

1. Vaccine 1 [ https://www.codechef.com/DEC20B/problems/VACCINE1]
2. Even pair sum [ https://www.codechef.com/DEC20B/problems/EVENPSUM]
3. Vaccine 2 [ https://www.codechef.com/DEC20B/problems/VACCINE2]
4. Positive Prefixes [ https://www.codechef.com/DEC20B/problems/POSPREFS]

Day15

1. A - favourite sequence [ https://codeforces.com/contest/1462/problem/A]
2. B - Last Year's Substring [ https://codeforces.com/contest/1462/problem/B ]
3. C - Unique Number [ https://codeforces.com/contest/1462/problem/C]
4. Square of sorted array [ https://leetcode.com/problems/squares-of-a-sorted-array/]

Day16

1. D- Add to Neighbours and Remove [ https://codeforces.com/contest/1462/problem/D]

Day17

1. 4Sum II [ https://leetcode.com/explore/challenge/card/december-leetcoding-challenge/571/week-3-december-15th-december-21st/3569/]
2. REC15A [ https://www.codechef.com/RC152020/problems/REC15A]

Day18

1. A- Dungeon [ https://codeforces.com/contest/1463/problem/A]
2. B- Find The Array [ https://codeforces.com/contest/1463/problem/B]
3. Incraesing Triplet Subsequence [ https://leetcode.com/problems/increasing-triplet-subsequence/]
4. Permutations [ https://leetcode.com/problems/permutations/]
5. Training [ https://codingcompetitions.withgoogle.com/kickstart/round/0000000000050e01/00000000000698d6]

Day19

1. A- Brick [ https://atcoder.jp/contests/abc186/tasks/abc186_a]
2. B- Blocks on Grid [ https://atcoder.jp/contests/abc186/tasks/abc186_b]
3. C- Unlucky 7 [ https://atcoder.jp/contests/abc186/tasks/abc186_c]
4. D- Sum of Difference [ https://atcoder.jp/contests/abc186/tasks/abc186_d]
5. Array swaps [ https://www.codechef.com/UWCOI21/problems/UWCOI21B]
6. Hidden Numbers [ https://www.codechef.com/UWCOI21/problems/UWCOI21A]
7. Efficient Delivery [ https://www.codechef.com/UWCOI21/problems/UWCOI21D]

Day20

1. A. In-game Chat [ https://codeforces.com/contest/1465/problem/A]
2. B. Fair Numbers [ https://codeforces.com/contest/1465/problem/B]
3. B. Move and Turn [ https://codeforces.com/contest/1459/problem/B]

Day21

1. Maximum Erasure Value [ https://leetcode.com/problems/maximum-erasure-value/]
2. Reformat Phone Number [ https://leetcode.com/problems/reformat-phone-number/]

Day22

1. Self-Destructing Strings [ https://www.codechef.com/COOK125A/problems/SDSTRING]

Day23

1. Choco Prime [ https://www.codechef.com/NQST2020/problems/CPRIME]
2. Help Santa [ https://www.codechef.com/NQST2020/problems/HELPSANT]
3. Ice Wrapped Sweets [ https://www.codechef.com/NQST2020/problems/ICEWRAP]
4. Next Greater Element III [https://leetcode.com/problems/next-greater-element-iii/]

Day24

1. Minimum Attendance Requirement [ https://www.codechef.com/COOK125A/problems/ATTENDU]
2. Catch the thief [ https://www.codechef.com/COOK125A/problems/CATHIEF]
3. Swap Nodes in Pairs [ https://leetcode.com/problems/swap-nodes-in-pairs/]

Day25

1. Four Segments [ https://codeforces.com/contest/1468/problem/E]
2. Waste sorting [ https://codeforces.com/contest/1468/problem/N]

Day26

1. Average wating time [ https://leetcode.com/problems/average-waiting-time/]
2. Number of students unable to eat lunch [https://leetcode.com/problems/number-of-students-unable-to-eat-lunch/]
3. Maximum binary string after change [https://leetcode.com/problems/maximum-binary-string-after-change/]
4. Multiple occurences [https://www.hackerearth.com/practice/basic-programming/implementation/basics-of-implementation/practice-problems/algorithm/multiple-occurence-97c00160/]
5. The Minimum Cost [ https://www.hackerearth.com/practice/basic-programming/bit-manipulation/basics-of-bit-manipulation/practice-problems/algorithm/min-cost-2-fe2d3308/]

Day27

1. Maximum occuring digit [ https://practice.geeksforgeeks.org/contest-problem/number-with-max-occourence-of-digit-k/1/]
2. Maximum sum contihuous subarray [ https://practice.geeksforgeeks.org/contest-problem/b882a3ac7c399bd0a328104fdc7c198edeee30e5/1/]
3. One Zero swaps [ https://www.codechef.com/LTIME91A/problems/SWAP10HG]
4. Three Letters [ https://www.codechef.com/LTIME91A/problems/THREE]
5. Sed Sequences [ https://www.codechef.com/LTIME91A/problems/SEDARR]
6. Special Square [ https://codedrills.io/contests/amrita-icpc-practice-session-2/problems/special-square]
7. Pattern A [ https://www.codechef.com/PTRN2020/problems/ITGUY35]
8. Pattern C [https://www.codechef.com/PTRN2020/problems/ITGUY37]
9. Pattern D [ https://www.codechef.com/PTRN2020/problems/ITGUY38]
10. Pattern E [ https://www.codechef.com/PTRN2020/problems/ITGUY39]
11. Pattern F [ https://www.codechef.com/PTRN2020/problems/ITGUY40]
12. Pattern I [https://www.codechef.com/PTRN2020/problems/ITGUY43]
13. Pattern J [ https://www.codechef.com/PTRN2020/problems/ITGU44]

Day28

1. First and last position of element in sorted order [ https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/]
2. A. Regular Bracket Sequence [ https://codeforces.com/contest/1469/problem/A]

Day29

1. B. Red and Blue [ https://codeforces.com/contest/1469/problem/B]
2. The Begining Era Of Cyberverse [ https://www.codechef.com/BYTR20A/problems/CYBV]
3. Cybalphabit [ https://www.codechef.com/BYTR20A/problems/CAB]

Day30

1. A. Bovine Delima [ https://codeforces.com/contest/1466/problem/A]
2. B. Last minute enhancements [ https://codeforces.com/contest/1466/problem/B]

Day31

1. C. Canine Poetry [ https://codeforces.com/contest/1466/problem/C]
2. Pseudo Plaindromic paths in a Binary Tree [ https://leetcode.com/problems/pseudo-palindromic-paths-in-a-binary-tree/]
3. Largest Rectangle in Histogram [ https://leetcode.com/problems/largest-rectangle-in-histogram/]

Day32

1. Check Array Formation Through Concatenation [ https://leetcode.com/problems/check-array-formation-through-concatenation/]

Day33

1. A - Large Digits [https://atcoder.jp/contests/abc187/tasks/abc187_a]
2. B - Gentle Piars [https://atcoder.jp/contests/abc187/tasks/abc187_b]
3. C - 1SAT [ https://atcoder.jp/contests/abc187/tasks/abc187_c]
4. D - Choose me [ https://atcoder.jp/contests/abc187/tasks/abc187_d]
5. Make the Array even https://www.hackerearth.com/practice/basic-programming/bit-manipulation/basics-of-bit-manipulation/practice-problems/algorithm/make-even-8ced0d4b/]
6. Maximum Profit [ https://www.hackerearth.com/problem/algorithm/maximum-profit-5-c3c2ce7c/]
7. Mathematically Beautiful Numbers [https://www.hackerearth.com/practice/basic-programming/implementation/basics-of-implementation/practice-problems/algorithm/mathematically-beautiful-numbers-174a158e/]

Day34

1. Maximum Units on a Truck [ https://leetcode.com/problems/maximum-units-on-a-truck/]
2. Count Good Meals [ https://leetcode.com/problems/count-good-meals/]

Day35

1. A - Cards for friends [ https://codeforces.com/contest/1472/problem/A]
2. B - Fair Division [ https://codeforces.com/contest/1472/problem/B]
3. C - Long Jumps [https://codeforces.com/contest/1472/problem/C]
4. D - Even Odd Game [ https://codeforces.com/contest/1472/problem/D]
5. Merge two sorted list [https://leetcode.com/explore/challenge/card/january-leetcoding-challenge-2021/579/week-1-january-1st-january-7th/3592/]

Day36

1. A - Strange Partition [ https://codeforces.com/contest/1471/problem/A]
2. B - Strange List [ https://codeforces.com/contest/1471/problem/B]

Day37

1. C - Strange Birthday Party [https://codeforces.com/contest/1471/problem/C]
2. Kth Missing Positive Number [https://leetcode.com/problems/kth-missing-positive-number/]

Day38

1. C- Divison [https://codeforces.com/contest/1445/problem/C]
2. Longest substring without repeating characters [https://leetcode.com/problems/longest-substring-without-repeating-characters/]

Day39

1. A - Wizard of Orz [ https://codeforces.com/contest/1467/problem/A]
2. B - Hills and Valley [ https://codeforces.com/contest/1467/problem/B]
3. Check if two strings are equivalent [https://leetcode.com/problems/check-if-two-string-arrays-are-equivalent/]

Day40

1. Simple math 2 [ https://atcoder.jp/contests/arc111/tasks/arc111_a]
2. Calculate money of leetcode bank [https://leetcode.com/problems/calculate-money-in-leetcode-bank/]
3. Maximum score from removing substring [https://leetcode.com/problems/maximum-score-from-removing-substrings/]
4. BuyOneGetOneFree [ https://arena.topcoder.com/#/u/coding/18435/16754/2]
5. Organic Chemistry [ https://arena.topcoder.com/#/u/coding/18435/16669/2]

Day41

1. Three point short [ https://atcoder.jp/contests/abc188/tasks/abc188_a]
2. Orthogonality [ https://atcoder.jp/contests/abc188/tasks/abc188_b]
3. Decode Xored Array [ https://leetcode.com/contest/weekly-contest-223/problems/decode-xored-array/]
4. Swapping nodes in linked list [ https://leetcode.com/contest/weekly-contest-223/problems/swapping-nodes-in-a-linked-list/]

Day42

1. Merge sorted Array [ https://leetcode.com/problems/merge-sorted-array/]

Day43

1. Add two numbers [ https://leetcode.com/problems/add-two-numbers/]
2. Fair selection [ https://www.codechef.com/problems/FAIRELCT]

Day44

1. Boats to save people [ https://leetcode.com/problems/boats-to-save-people/]
2. Container with most warter [ https://leetcode.com/problems/container-with-most-water/]
3. Chef and Division 3 [ https://www.codechef.com/problems/DIVTHREE]

Day45

1. A - Replacing elements [ https://codeforces.com/contest/1473/problem/A]
2. B - String Lcm [ https://codeforces.com/contest/1473/problem/B]
3. C - No more inversions [https://codeforces.com/contest/1473/problem/C]

Day46

1. Climbing stairs [https://leetcode.com/problems/climbing-stairs/]
2. Fibonacci number [https://leetcode.com/problems/fibonacci-number/]
3. Get maximum in generated array [https://leetcode.com/problems/get-maximum-in-generated-array/]
4. Friend Finder
5. Paired Multiple

Day47

1. A - Two sequences 2 [https://atcoder.jp/contests/keyence2021/tasks/keyence2021_a]
2. B - Mex Boxes [https://atcoder.jp/contests/keyence2021/tasks/keyence2021_b]
3. Kth largest element in array [https://leetcode.com/problems/kth-largest-element-in-an-array/]

Day48

1. Number of rectangles that can form the largest square [https://leetcode.com/problems/number-of-rectangles-that-can-form-the-largest-square/]
2. Tuple with same product [https://leetcode.com/problems/tuple-with-same-product/]
3. Count sorted vowels string [ https://leetcode.com/problems/count-sorted-vowel-strings/]

Day49

1. Delete Node in BST [https://leetcode.com/problems/delete-node-in-a-bst/]
2. Max Number of K sum pairs [https://leetcode.com/problems/max-number-of-k-sum-pairs/]

Day50

1. Longest Palindromic substring [ https://leetcode.com/problems/longest-palindromic-substring/]
2. A - Puzzle from future [https://codeforces.com/contest/1474/problem/A]
3. B - Different Divisors [https://codeforces.com/contest/1474/problem/B]

Day51

1. Valid Parentheses [https://leetcode.com/problems/valid-parentheses/]

Day52

1. find the most competitive sequence [https://leetcode.com/problems/find-the-most-competitive-subsequence/]
2. Number Guessing [ https://codingcompetitions.withgoogle.com/kickstart/round/0000000000051060/00000000000588f4]
3. Mural [https://codingcompetitions.withgoogle.com/kickstart/round/0000000000051060/0000000000058b89]
4. Building Palindromes [https://codingcompetitions.withgoogle.com/kickstart/round/0000000000050eda/0000000000119866]

Day53

1. Determine if two strings are close [https://leetcode.com/explore/challenge/card/january-leetcoding-challenge-2021/582/week-4-january-22nd-january-28th/3613/]

Day54

1. A - Slot [https://atcoder.jp/contests/abc189/tasks/abc189_a]
2. B - Alcoholic [https://atcoder.jp/contests/abc189/tasks/abc189_b]
3. C - Mandarin Orange [https://atcoder.jp/contests/abc189/tasks/abc189_c]
4. Decode Xored Array [https://leetcode.com/problems/decode-xored-permutation/]
5. Find the Highest Altitude [https://leetcode.com/contest/biweekly-contest-44/problems/find-the-highest-altitude/]

Day55

1. Latest Time By replacing hidden digits [https://leetcode.com/problems/latest-time-by-replacing-hidden-digits/]
2. Find the kth Xored Array [https://leetcode.com/problems/find-kth-largest-xor-coordinate-value/]
3. A chessboard https://www.hackerearth.com/practice/algorithms/greedy/basics-of-greedy-algorithms/practice-problems/algorithm/chessboard-2-8f06e380/]
4. The GCD Function [https://www.hackerearth.com/problem/algorithm/gcd-function-9fe49c14/]
5. Replace the String [ https://www.hackerearth.com/practice/algorithms/string-algorithm/string-searching/practice-problems/algorithm/make-them-equal-ac0bab4a/]
6. Scoreboard Queries [https://www.hackerearth.com/practice/data-structures/arrays/1-d/practice-problems/algorithm/tournament-and-ranks-67cd4b7e/]

Day56

1. A - Odd Divisors [https://codeforces.com/contest/1475/problem/A]
2. B - New Year's Number [https://codeforces.com/contest/1475/problem/B]
3. Prime Tuples [https://www.codechef.com/COOK126B/problems/PTUPLES]
4. Maximise Islands [https://www.codechef.com/COOK126B/problems/MINIL]
5. Check if all 1's are atleast length K places away [ https://leetcode.com/problems/check-if-all-1s-are-at-least-length-k-places-away/]

Day57

1. Min Sum ( Codenation innovation labs Hiring contest ) [https://codeforces.com/blog/entry/87234]

Day58

1. Bit Queries ( Codenation innovation labs Hiring Contest ) [https://codeforces.com/blog/entry/87234]
2. A - Directional move [https://codeforces.com/gym/102942/problem/A]
3. B - Make all odd [https://codeforces.com/gym/102942/problem/B]
4. C - Team [https://codeforces.com/gym/102942/problem/C]
5. D - XOR Game [https://codeforces.com/gym/102942/problem/D]

Day59

1. A - Nezzar and Colorful Balls [ https://codeforces.com/contest/1478/problem/A]
2. Triangles [https://www.e-olymp.com/en/contests/19316/problems/207756]
3. Mad Scientist [https://www.e-olymp.com/en/contests/19316/problems/207757]
4. Smallest string with a given numeric value [https://leetcode.com/problems/smallest-string-with-a-given-numeric-value/]
5. B. Nezzar and Lucky Number [ https://codeforces.com/contest/1478/problem/B]

Day60

1. Vertical order traversal of binary tree [https://leetcode.com/problems/vertical-order-traversal-of-a-binary-tree/]
2. A - K Divisible sum [https://codeforces.com/contest/1476/problem/A]
3. B - Inflation [https://codeforces.com/contest/1476/problem/B]

Day61

1. A - Very Very Primitive Game [https://atcoder.jp/contests/abc190/tasks/abc190_a]
2. B - Magic3 [https://atcoder.jp/contests/abc190/tasks/abc190_b]
3. D - Staircase Sequence [https://atcoder.jp/contests/abc190/tasks/abc190_d]
4. Discount in shop [https://www.codechef.com/AIMICPC?itm_campaign=contest_listing]
5. Select Training Set [https://www.codechef.com/AIMICPC?itm_campaign=contest_listing]

Day62

1. Even Difference [https://www.codechef.com/LTIME92B/problems/EVENDIFF]
2. Even sum [https://www.codechef.com/LTIME92B/problems/EVENGAME]
3. Palindrome Partitioning IV [ https://leetcode.com/problems/palindrome-partitioning-iv/]
4. Restore Array from Adjacent pairs [https://leetcode.com/problems/restore-the-array-from-adjacent-pairs/]
5. Maxinum number of Balls in Box [https://leetcode.com/problems/maximum-number-of-balls-in-a-box/]

Day63

1. Binary Subsequence [https://www.codechef.com/LTIME92B/problems/BINSUBS]
2. Dreams of Divisibility [ https://www.codechef.com/LTIME92B/problems/DREDIV]
3. Number of 1 Bits [https://leetcode.com/problems/number-of-1-bits/]

Day64

1. Trim a Binary Search Tree [https://leetcode.com/problems/trim-a-binary-search-tree/]

Day65

1. Lined List Cycle [https://leetcode.com/problems/linked-list-cycle/]
2. Metreology stataion [https://www.codechef.com/problems/CHEFTEMP]

Day66

1. Longest Harmonic Subsequence [https://leetcode.com/problems/longest-harmonious-subsequence/]
2. Longest Common Prefix [https://leetcode.com/problems/longest-common-prefix/]

Day67

1. Grid Escape [https://codingcompetitions.withgoogle.com/codejamio/round/0000000000050fc5/0000000000054e9c]
2. A - Space Navigation [https://codeforces.com/contest/1481/problem/A]
3. B - New Colony [https://codeforces.com/contest/1481/problem/B]
4. Create Targeted Array in Given Order [https://leetcode.com/problems/create-target-array-in-the-given-order/]

Day68

1. A - Vanish Pitch [https://atcoder.jp/contests/abc191/tasks/abc191_a]
2. B - Remove it [https://atcoder.jp/contests/abc191/tasks/abc191_b]
3. Binary Tree Right side View [https://leetcode.com/problems/binary-tree-right-side-view/]
4. Minimum Length of string after deleting similar ends [https://leetcode.com/problems/minimum-length-of-string-after-deleting-similar-ends/]
5. Maximum Absolute sum of any subarray [https://leetcode.com/problems/maximum-absolute-sum-of-any-subarray/]
6. Sum of Unique Elements [https://leetcode.com/problems/sum-of-unique-elements/]

Day69

1. Check if Array is Sorted and Rotated [https://leetcode.com/problems/check-if-array-is-sorted-and-rotated/]
2. Maximum Score from removing stones [https://leetcode.com/problems/maximum-score-from-removing-stones/]
3. Largest Merge of Two string [https://leetcode.com/problems/largest-merge-of-two-strings/]
4. A - Yet Another string Game [https://codeforces.com/contest/1480/problem/A]
5. Shortest Distance to a Character [https://leetcode.com/problems/shortest-distance-to-a-character/]

Day70

1. Remove Element [ https://leetcode.com/problems/remove-element/]

Day71

1. MAXFUN [https://www.codechef.com/FEB21B/problems/MAXFUN]
2. Frog Sort [https://www.codechef.com/FEB21B/problems/FROGS]
3. Team Name [https://www.codechef.com/FEB21B/problems/TEAMNAME]
4. Convert BST to Greater Tree [https://leetcode.com/problems/convert-bst-to-greater-tree/]

Day72

1. Alice and Candies [https://www.hackerearth.com/practice/math/number-theory/basic-number-theory-1/practice-problems/algorithm/lola-and-candies-36b57b1b/]
2. Deleting Arrays [https://www.hackerearth.com/practice/algorithms/greedy/basics-of-greedy-algorithms/practice-problems/algorithm/array-deletion-2-aee9dffe/]

Day73

1. PRIMEGAME [ https://www.codechef.com/FEB21B/problems/PRIGAME]
2. Valid Anagram [https://leetcode.com/problems/valid-anagram/]

Day74

1. Number of Steps to Reduce a Number to Zero [ https://leetcode.com/problems/number-of-steps-to-reduce-a-number-to-zero/]
2. A - Add and Divide [ https://codeforces.com/contest/1485/problem/A]
3. B - Replace and Keep Sorted [ https://codeforces.com/contest/1485/problem/B]

Day75

1. A-B=C [ https://atcoder.jp/contests/arc112/tasks/arc112_a]
2. TIEFighterAssembly [https://arena.topcoder.com/#/u/viewCode/18497/170065/2/335462/pkpawan/details]

Day76

1. SlotMachineHacking [https://arena.topcoder.com/#/u/viewCode/18497/170071/2/335462/pkpawan/details]
2. Minimum Changes to make alternating binary string [https://leetcode.com/problems/minimum-changes-to-make-alternating-binary-string/]
3. Count number of homogeneous strings [https://leetcode.com/problems/count-number-of-homogenous-substrings/]

Day77

1. A - Arena [https://codeforces.com/contest/1487/problem/A]

Day78

1. The Kth Weakest Row in Matrix [https://leetcode.com/problems/the-k-weakest-rows-in-a-matrix/]

Day79

1. Conntainer with most water [https://leetcode.com/problems/container-with-most-water/]
2. A - Dense Array [https://codeforces.com/contest/1490/problem/A]
3. B - Balanced Remainders [https://codeforces.com/contest/1490/problem/B]
4. C - Sum of Cubes [https://codeforces.com/contest/1490/problem/C]
5. D - Permutation Transformation [https://codeforces.com/contest/1490/problem/D]

Day80

1. B - Cat Cycle [https://codeforces.com/contest/1487/problem/B]
2. A - Shifting stacks [https://codeforces.com/contest/1486/problem/A]
3. E - Accidental Victory [https://codeforces.com/contest/1490/problem/E]
4. Arithmetic Slices [https://leetcode.com/explore/challenge/card/february-leetcoding-challenge-2021/586/week-3-february-15th-february-21st/3644/]

Day81

1. B - Eastern Exhibition [https://codeforces.com/contest/1486/problem/B]
2. Minimum remove to make valid parentheses [https://leetcode.com/problems/minimum-remove-to-make-valid-parentheses/]

Day82

1. A - Star [https://atcoder.jp/contests/abc192/tasks/abc192_a]
2. B - uNrEaDaBlE sTrInG [https://atcoder.jp/contests/abc192/tasks/abc192_b]
3. C - Kaprekar Number [https://atcoder.jp/contests/abc192/tasks/abc192_c]

Day83

1. Form Array by Concatenating Subarrays of Another Array [https://leetcode.com/problems/form-array-by-concatenating-subarrays-of-another-array/]
2. Merge string Alternately [https://leetcode.com/problems/merge-strings-alternately/]
3. Minimum number of operation sto move all ball to each box [https://leetcode.com/problems/minimum-number-of-operations-to-move-all-balls-to-each-box/]
4. Broken Calculator [https://leetcode.com/problems/broken-calculator/]

Day84

1. Longest word in Dictionary through deleting [https://leetcode.com/problems/longest-word-in-dictionary-through-deleting/]
2. Robotic moves [https://www.hackerearth.com/challenges/competitive/february-circuits-21-2/problems/]
3. The smallest permutation [https://www.hackerearth.com/challenges/competitive/february-circuits-21-2/problems/]

Day85

1. A - Three swimmers [https://codeforces.com/contest/1492/problem/A]
2. The smallest string [https://www.hackerearth.com/challenges/competitive/february-circuits-21-2/problems/]

Day86

1. BMI [https://www.codechef.com/CCRC21B/problems/BMI]
2. CHEFPAT [https://www.codechef.com/CCRC21B/problems/CHEFPAT]
3. TOTSCR [https://www.codechef.com/CCRC21B/problems/TOTSCR]

Day87

1. A Xor Value [https://www.hackerearth.com/challenges/competitive/february-circuits-21-2/problems/]

Day88

1. Shortest unsoted contiguous array [https://leetcode.com/problems/shortest-unsorted-continuous-subarray/]
2. Validate stack sequence [https://leetcode.com/problems/validate-stack-sequences/]

Day89

1. A - Broken Keyboard [https://www.hackerearth.com/challenges/competitive/february-circuits-21-2/problems/]
2. Array Operations [https://www.hackerearth.com/challenges/competitive/february-circuits-21-2/problems/]
3. B - Card Deck [https://codeforces.com/contest/1492/problem/B]

Day90

1. Count items matching rule [https://leetcode.com/problems/count-items-matching-a-rule/]
2. Equal sum Arrays with Minimum number of operation [https://leetcode.com/problems/equal-sum-arrays-with-minimum-number-of-operations/]

Day91

1. A - kth Largest Value [https://codeforces.com/contest/1491/problem/A]
2. B - minimal Cost [https://codeforces.com/contest/1491/problem/B]
3. Distribute Candies [https://leetcode.com/problems/distribute-candies/]

Day92

1. A - ABC string [https://codeforces.com/contest/1494/problem/A]
2. Set Mismatch [https://leetcode.com/problems/set-mismatch/]

Day93

1. Chef and Coupon (COUPON2) [https://www.codechef.com/START1B/problems/COUPON2]
2. Maximum Value [https://www.codechef.com/START1B/problems/MVALUE]
3. Missing Number [https://leetcode.com/problems/missing-number/]

Day94

1. Intersection of two linked list [https://leetcode.com/explore/challenge/card/march-leetcoding-challenge-2021/588/week-1-march-1st-march-7th/3660/]

Day95

1. Average Levels in Binary Tree [https://leetcode.com/explore/challenge/card/march-leetcoding-challenge-2021/588/week-1-march-1st-march-7th/3661/]

Day96

1. A - Anti Knapsack [https://codeforces.com/contest/1493/problem/A]
2. A - IScream [https://atcoder.jp/contests/abc194/tasks/abc194_a]
3. B - Job Asignment [https://atcoder.jp/contests/abc194/tasks/abc194_b]
4. C - Squared error [https://atcoder.jp/contests/abc194/tasks/abc194_c]
5. Check if number is sum of power of 3 [https://leetcode.com/problems/check-if-number-is-a-sum-of-powers-of-three/]
6. Find the nearest point that has same X or Y coordinate [https://leetcode.com/problems/find-nearest-point-that-has-the-same-x-or-y-coordinate/]

Day97

1. Minimum element to add to given sum [https://leetcode.com/problems/minimum-elements-to-add-to-form-a-given-sum/]
2. check if binary string has atmost one segment of ones [https://leetcode.com/problems/check-if-binary-string-has-at-most-one-segment-of-ones/]
3. Binary tree level order traversal [https://leetcode.com/problems/binary-tree-level-order-traversal/]
4. Binary tree zig zag level order traversal [https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/]

Day98

1. B - Planet Lapituletti [https://codeforces.com/contest/1493/problem/B]
2. Tidy Numbers [https://codingcompetitions.withgoogle.com/codejam/round/00000000002017f7/0000000000201878]
3. Oversized Pancake Flipper [https://codingcompetitions.withgoogle.com/codejam/round/00000000002017f7]

Day99

1.Counting sheeps [https://codingcompetitions.withgoogle.com/codejam/round/0000000000201bee/0000000000201c8a] 2. Revenge of Pancake [https://codingcompetitions.withgoogle.com/codejam/round/0000000000201bee/0000000000201c8a]

Day100

1. A - split it! [https://codeforces.com/contest/1496/problem/A]
2. B - Mex and Max [https://codeforces.com/contest/1496/problem/B]
3. C - Diamond Miner [https://codeforces.com/contest/1496/problem/C]