实现拥有重复元素的二分查找法

github 莫名其妙的打不开了，那就贴在这里吧

#!/usr/bin/env python# -*- #coding:utf-8'''Created on 2013-9-4@author: mingdong.li二分查找法,有相同元素列表'''import unittestfrom test.test_bisect import TestErrorHandlingfrom test import test_support_searchMode = {"FIRST":1, "LAST":0}def binarySearchTemplate(sequence, fromIndex, toIndex, key, searchMode):    """    @param sequence: is a list or tuple to be searched, it's sequential and no repeating elements    @param fromIndex: the index of the first element to be searched    @param toIndex: the index of the last element to be searched    @param key: the value to be searched for    @param searchMode: FIRST=1(return the index of the first element in the repeating sequence); LAST=0(the last one)     @return: index of the search key, no found will return -1    """    low = fromIndex    high = toIndex - 1    flag = -1    while(low <= high):        mid = low + ((high-low)>>1)        midValue = sequence[mid]        if midValue < key:            low = mid + 1        elif midValue > key:            high = mid -1        else:            if searchMode is None:                return mid            elif searchMode == _searchMode['FIRST']:                high = mid - 1                flag = mid            elif searchMode == _searchMode['LAST']:                low = mid + 1                flag = mid    else:        if searchMode == _searchMode['FIRST']:            if key == sequence[high]:#                print 'first high'                return high            else:#                print 'first flag'                return flag        elif searchMode == _searchMode['LAST']:            if key == sequence[low-1]:#                print 'last high'                return low-1            else:#                print 'last flag'                return flag        else:            return -1#        return -1def binarySearch(sequence, key, searchMode=None):    if not isinstance(sequence, list) and not isinstance(sequence, tuple):        return "The %s is not list or tuple" % sequence    return binarySearchTemplate(sequence, 0, len(sequence), key, searchMode) def test_main(verbose=None):        class TestBinarySearch(unittest.TestCase):        a = [1, 1, 1, 2, 2, 3, 4, 4, 4, 5, 6, 7, 7, 7, 7, 7]        b = (1, 1, 1, 2, 2, 3, 4, 4, 4, 5, 6, 7, 7)        precomputedCase = [            (binarySearch, 'a', 88, None, "The a is not list or tuple"),            (binarySearch, a, 2, None, 3),            (binarySearch, a, 88, None, -1),            (binarySearch, a, 7, _searchMode['FIRST'], 11),            (binarySearch, a, 7, _searchMode['LAST'], 15),            (binarySearch, a, 1, _searchMode['FIRST'], 0),            (binarySearch, a, 1, _searchMode['LAST'], 2),            (binarySearch, a, 4, _searchMode['FIRST'], 6),            (binarySearch, a, 11, _searchMode['FIRST'], -1),            (binarySearch, a, 11, _searchMode['LAST'], -1),                        (binarySearch, b, 2, None, 4),            (binarySearch, b, 88, None, -1),            (binarySearch, b, 7, _searchMode['FIRST'], 11),            (binarySearch, b, 7, _searchMode['LAST'], 12),            (binarySearch, b, 1, _searchMode['FIRST'], 0),            (binarySearch, b, 1, _searchMode['LAST'], 2),            (binarySearch, b, 4, _searchMode['FIRST'], 6),            (binarySearch, b, 11, _searchMode['FIRST'], -1),            (binarySearch, b, 11, _searchMode['LAST'], -1)        ]                def test_precomputed(self):            for func, sequ, key, mode, expected in self.precomputedCase:                self.assertEqual(func(sequ, key, mode), expected)    from types import BuiltinFunctionType    test_classes = [TestBinarySearch]    if isinstance(binarySearch, BuiltinFunctionType):        test_classes.append(TestErrorHandling)        test_support.run_unittest(*test_classes)if __name__ == '__main__':    print "test..."    test_main(verbose=True)