现在回到我们的题目,虽然看上去互换(swap)非常迷惑,感觉非常像双向 graph,但实际上这是一个单向 graph 就可以解决的题目。解题思路所以我的思路如下,用标准的 DFS 来遍历这个 graph 即可。 ①首先建立 graph (index, num) [(0, 1), (1, 3), (2, 4), (3, 2)] ...
周赛地址(英):weekly contest 196 周赛地址(中):第 196 场周赛 仓库地址:week-Leetcode 1502. Can Make Arithmetic Progression From Sequence Given an array of numbers arr. A s
To scramble the string, we may choose any non-leaf node and swap its two children. For example, if we choose the node"gr"and swap its two children, it produces a scrambled string"rgeat". rgeat / \ rg eat / \ / \ r g e at / \ a t We say that"rgeat"is a scrambled string...
Swap Values:x ^= y; y ^= x; x ^= y; Runtime Analysis Big O Notationis used to describe the upper bound of a particular algorithm. Big O is used to describe worst case scenarios Little O Notationis also used to describe an upper bound of a particular algorithm; however, Little O ...