Top Interview 150第四天｜55. Jump Game，hashtable

55. Jump Gamehttps://leetcode.com/problems/jump-game/

topics：dynamic programming，greedy

solution1： greedy - local optimization --》 global optimization

贪心，每到一个位置就更新当前可到达的最远距离；初始化为起点0

56. Merge Intervalshttps://leetcode.com/problems/merge-intervals/

怎么给intervals排序？

intervals.sort( ) #Python 的sort()函数默认就会按照子列表的第一个元素（索引 0）进行排序，如果第一个相等，再比第二个。

sorted(intervals)

intervals.sort(key=lambda x: x[0])

205. Isomorphic Stringshttps://leetcode.com/problems/isomorphic-strings/

写出来mapping

dict = {}

for char1, char2 in zip(s, t):

s[char1] = char2

t[char2] = char1

290. Word Patternhttps://leetcode.com/problems/word-pattern/是205的升级模式，添加的东西时words = s.split(" ")

242. Valid Anagramhttps://leetcode.com/problems/valid-anagram/这道题还挺简单的

1. Two Sumhttps://leetcode.com/problems/two-sum/

暴力solution + hash table

for target - x in dict: #这里是找key in the dictionary

dict[x] = idx

202. Happy Numberhttps://leetcode.com/problems/happy-number/需要复习 - 没能一次写出来