class Solution:
def climbStairs(self, n: int) -> int:
def climb(n, x):
if n<0:
return 0
if n==0:
return 1
if x[n] != -1:
return x[n]
else:
x[n] = climb(n-1, x) + climb(n-2, x)
return x[n]
return climb(n, [-1] *(n+1))
90. Subsets II | 1560A - Dislike of Threes |
36. Valid Sudoku | 557. Reverse Words in a String III |
566. Reshape the Matrix | 167. Two Sum II - Input array is sorted |
387. First Unique Character in a String | 383. Ransom Note |
242. Valid Anagram | 141. Linked List Cycle |
21. Merge Two Sorted Lists | 203. Remove Linked List Elements |
733. Flood Fill | 206. Reverse Linked List |
83. Remove Duplicates from Sorted List | 116. Populating Next Right Pointers in Each Node |
145. Binary Tree Postorder Traversal | 94. Binary Tree Inorder Traversal |
101. Symmetric Tree | 77. Combinations |
46. Permutations | 226. Invert Binary Tree |
112. Path Sum | 1556A - A Variety of Operations |
136. Single Number | 169. Majority Element |
119. Pascal's Triangle II | 409. Longest Palindrome |
1574A - Regular Bracket Sequences | 1574B - Combinatorics Homework |