剣指offer全集詳しくpython版--数字がソート配列に現れる回数

# -*- coding:utf-8 -*-
class Solution:
    def GetNumberOfK(self, data, k):
        # write code here
        if not data:
            return 0
        low = 0
        high = len(data) - 1
        cnt = 0
        end = len(data) - 1
        while low <= high:
            medium = (low + high) / 2
            if data[medium] == k:
                # print "medium: ", medium
                #                    
                while medium >= 0 and data[medium] == k:
                    medium -= 1
                medium += 1
                # print "left: ", medium
                while medium <= end and data[medium] == k:
                    medium += 1
                    cnt += 1
                return cnt
            elif data[medium] < k:
                low = medium + 1
            else:
                high = medium - 1
        return cnt