归档 2015年11月

题目描述：

Given n balloons, indexed from 0 to n-1. Each balloon is painted with a number on it represented by array nums. You are asked to burst all the balloons. If you burst balloon i you will get nums[left ...

题目描述：

Given a binary tree, find its minimum depth.

The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node.

题目大意：

给定一棵二叉树，计算其最小深度。

最小深度是指从根节点出发到达最近的叶子节点所需要经过的节点个数。

解题思路：

DFS或者BFS均可，详见代码。

Python代码（DFS ...

题目描述：

For a undirected graph with tree characteristics, we can choose any node as the root. The result graph is then a rooted tree. Among all possible rooted trees, those with minimum height are called minimum height trees (MHTs). Given ...

题目描述：

Say you have an array for which the i-th element is the price of a given stock on day i.

Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy ...

字符切分是实现机器识别验证码的一个必要步骤。

使用PIL读入图像，进行二值化处理（Binarize），然后利用sklearn.cluster中的kmeans进行字符切分，最后用matplotlib.pyplot输出结果。

参考：http://dsp.stackexchange.com/questions/23662/k-means-for-2d-point-clustering-in-python

Python代码：

import numpy as np
import matplotlib.pyplot as plt
from sklearn.cluster import KMeans
from PIL import Image

##############################################################################
# Binarize image data

im = np ...