warmup, preparing to give interviews

src/builtin_structures/combinations.py

@@ -1,26 +0,0 @@
-#!/usr/bin/env python
-
-__author__ = "bt3"
-
-
-def combinations(s):
-    '''
-    >>> combinations('abc')
-    ['abc', 'acb', 'bac', 'bca', 'cab', 'cba']
-    >>> combinations('')
-    ''
-    '''
-    if len(s) < 2:
-        return s
-    res = []
-    for i, c in enumerate(s):
-        res.append(c)
-        for j in combinations(s[:i] + s[i+1:]):
-            res.append(c + j)
-    return res
-
-
-
-if __name__ == '__main__':
-    import doctest
-    doctest.testmod()

src/builtin_structures/find_longest_common_prefix.py

@@ -1,76 +0,0 @@
-#!/usr/bin/env python
-
-__author__ = "bt3"
-
-
-'''
-Given two strings, write a function
-to calculate the longest common prefix (LCP) of the strings.
-'''
-
-def lcp(s1, s2):
-    '''
-    >>> lcp('dabbd', 'aabbaa')
-    3
-    >>> lcp('abcd', 'hi')
-    0
-    '''
-
-    p1 = 0
-    aux, lcp = '', ''
-    string1 = min(s1, s2)
-    string2 = max(s1, s2)
-
-    while p1 < len(string1):
-        p2 = 0
-        while  p2 < len(string2) and p1+p2 < len(string1):
-            if string1[p1+p2] == string2[p2]:
-                aux += string1[p1+p2]
-            else:
-                if len(lcp) < len(aux):
-                    lcp = aux
-                aux = ''
-            p2 += 1
-        p1 += 1
-
-    return len(lcp)
-
-
-
-def lcppy(x):
-    '''
-    >>> lcppy([[3,2,1], [3,2,1,4,5]])
-    [3, 2, 1]
-    '''
-    import os
-    return os.path.commonprefix(x)
-
-
-def lcp2(s1, s2):
-    '''
-    >>> lcp2('dabbd', 'aabbaa')
-    3
-    >>> lcp2('abcd', 'hi')
-    0
-    '''
-    m = [[0 for i in range(len(s2) + 1)] for k in range(len(s1) + 1)]
-
-    lcp = 0
-
-    for y in range(1, len(s1) + 1):
-        for x in range(1, len(s2) + 1):
-            if (s1[y - 1] == s2[x - 1]):
-                m[y][x] = m[y - 1][x - 1] + 1
-            else:
-                m[y][x] = 0
-
-            if m[y][x] > lcp:
-                lcp = m[y][x]
-    return lcp
-
-
-
-if __name__ == '__main__':
-    import doctest
-    doctest.testmod()
-