zevolo的专栏

!/usr/bin/python '''file name: inversion.py --P41 --calculate the inversion number in nlgn for the worse situation --author: zevolo, 2012.05.07 ''' global count def merge_sort(list, s, e):

算法导论学习，一些习题和算法的实现（python版） 第三版，英文版

O(n) #!/usr/bin/python '''file name: maxsum.py --P75 --find maximum subarray sum, O(n) --author: zevolo, 2012.05.11 ''' def find_max_sum(list): now_max = list[0] low = high = 0

monge array是一个矩阵，满足第j行的最小值的列号C(j)大于等于第i行的最小值的列号C(i)，当j>=i的时候，有如下特性 －－ 对于任何行列，正对角线的和 #!/usr/bin/python '''file name: monge.py --P111 --input one m*n monge array, find leftmost minimum value, O

算法导论（3版）第5章 习题解答  by zevolo 5.2-3 indicator random variable set X(i) = I(i)     = 1  (when ith dot is show)       0  (when ith dot is hide) Now E(X) = E(X(1)) + E(X(2)) + E(X(3)) + .... + E(X

#!/usr/bin/python '''file name: insertion_sort.py --P18 --insertion sort --author: zevolo, 2012.04.28 --modify on 06.07 for stable issue  ''' def insert(list): for i in range(1, len

O(nlgn) #!/usr/bin/python '''file name: maxsum.py --P71 --find maximum subarray sum, divide-and-conquer O(nlng) --author: zevolo, 2012.05.11 ''' def find_max_across_mid(list, low, high,

根据下面的公式计算的一些数据，方便查表

Introduction to algorithms (3rd editon) 第四章部分解答        by zevolo 4.3-1 Show that the solution of T(n) = T(n-1) + n is O(n^2). proof: assume  T(m) T(n) = T(n-1) + n          = cn^2 - 2cn + c