Basic LinkedList/ Array/ String

(1) Sort List (leetcode 148)
(2) Reverse List in K group (leetcode 25) try both recursive and iterative
(3) Merge K sorted List (leetcode 23)
(4) Insertion Sort List (leetcode 147) also try merge sort, quick sort

(5) Summary Ranges (leetcode 228)
(6) Merge Intervals (leetcode 56), Insert Interval (leetcode 57)
(7) Spiral Matrix (leetcode 54) II (leetcode 59), Rotate Image (leetcode 48)
(8) Longest consecutive Sequence (leetcode 128)
(9) Game of life (leetcode 289)
(10) Missing range (leetcode 163)
(11) Missing Number (leetcode 268), find all duplicate (0 ~ n-1)

(12) Text justification (leetcode 68)
(13) Simplify path (leetcode 71)
(14) Shortest Palindrome (leetcode 214) KMP
(15) read N character giving read4(leetcde157), II (leetcode 158)
(16) Integer to Roman (leetcode 12) Integer to English Words (leetcode 273)
(17) compare version number (leetcode 165)