题目描述

统计一个数字在升序数组中出现的次数。

  1. # -*- coding:utf-8 -*-
  2. class Solution:
  3.     def GetNumberOfK(self, data, k):
  4.         # write code here
  5.         def get_first(data,k):
  6.             l,r = 0,len(data)
  7.             while l<r:
  8.                 m = (l+r)/2
  9.                 if data[m]>=k:
  10.                     r = m
  11.                 else:
  12.                     l = m + 1
  13.             return l
  14.         first_index = get_first(data, k)
  15.         last_index = get_first(data, k + 1)
  16.         if first_index == len(data) or data[first_index]!=k:
  17.             return 0
  18.         else:
  19.             return last_index-first_index