Introduction
相信大家开始学习C/C++的时候,都会遇上memcpy
这个函数。简单来说这个是一个拷贝函数,使用方法很简单,但在今天这篇博客,我将来探讨一下里面的实现细节,尝试自己也实现一个具备基本功能的memcpy
。
There is an undirected connected tree with n
nodes labeled from 0
to n - 1
and n - 1
edges.
You are given the integer n
and the array edges
where edges[i] = [ai, bi]
indicates that there is an edge between nodes ai
and bi
in the tree.
Return an array answer
of length n
where answer[i]
is the sum of the distances between the ith
node in the tree and all other nodes.
You are given an array routes
representing bus routes where routes[i]
is a bus route that the ith
bus repeats forever.
routes[0] = [1, 5, 7]
, this means that the 0th
bus travels in the sequence 1 -> 5 -> 7 -> 1 -> 5 -> 7 -> 1 -> ...
forever.You will start at the bus stop source
(You are not on any bus initially), and you want to go to the bus stop target
. You can travel between bus stops by buses only.
Return the least number of buses you must take to travel from source
to target
. Return -1
if it is not possible.
You are given an array trees
where trees[i] = [xi, yi]
represents the location of a tree in the garden.
You are asked to fence the entire garden using the minimum length of rope as it is expensive. The garden is well fenced only if all the trees are enclosed.
Return the coordinates of trees that are exactly located on the fence perimeter.