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Python实现删除排序数组中重复项的两种方法示例

更新时间:2020-06-23 22:12:01 作者:startmvc
本文实例讲述了Python实现删除排序数组中重复项的两种方法。分享给大家供大家参考,具体

本文实例讲述了Python实现删除排序数组中重复项的两种方法。分享给大家供大家参考,具体如下:

对于给定的有序数组nums,移除数组中存在的重复数字,确保每个数字只出现一次并返回新数组的长度

注意:不能为新数组申请额外的空间,只允许申请O(1)的额外空间修改输入数组

Example 1:

Given nums = [1,1,2], Your function should return length = 2, with the first two elements of nums being 1 and 2 respectively. It doesn't matter what you leave beyond

Example 2:

Given nums = [0,0,1,1,1,2,2,3,3,4],Your function should return length = 5, with the first five elements of nums being modified to 0, 1, 2, 3, and 4 respectively. It doesn't matter what values are set beyond the returned length.

说明:为什么返回列表长度而不用返回列表?因为列表传入函数是以引用的方式传递的,函数中对列表进行的修改会被保留。


 // nums is passed in by reference. (i.e., without making a copy)
int len = removeDuplicates(nums);
// any modification to nums in your function would be known by the caller.
// using the length returned by your function, it prints the first len elements.
for (int i = 0; i < len; i++) {
 print(nums[i]);
}

1. 简单判断列表中元素是否相等,相等就删除多余元素


def removeDuplicates(self, nums):
 """
 :type nums: List[int]
 :rtype: int
 """
 if not nums:
 return 0
 if len(nums)==1: #单独判断列表长度为1的情况,因为之后的for循环从下标1开始
 return 1
 temp_num = nums[0]
 count =0 #for循环中动态删除列表元素,列表缩短,为了防止下标溢出需要用count标记删除元素个数
 for index, num in enumerate(nums[1:]):
 if temp_num == num: #元素相等就删除
 del nums[index-count]
 count += 1
 else:
 temp_num = num
 return len(nums)
def removeDuplicates(self, nums):
 """
 :type nums: List[int]
 :rtype: int
 """
 forth = 0
 back = 1
 while back <= len(nums)-1:
 if nums[forth] == nums[back]:
 nums.pop(back)
 else:
 forth += 1
 back += 1
 return len(nums)

2. 修改数组,保证数组的前几个数字互不相同,且这几个数字的长度同返回长度相等


def removeDuplicates(self, nums):
 """
 :type nums: List[int]
 :rtype: int
 """
 if not nums:
 return 0
 length = 0 #不存在重复数字的数组长度
 for index in range(1,len(nums)): #遍历数组
 if nums[index] != nums[length]:
 length += 1
 nums[length] = nums[index]
 return length+1

算法题来自:https://leetcode-cn.com/problems/remove-duplicates-from-sorted-array/description/

PS:本站还有两款比较简单实用的在线文本去重复工具,推荐给大家使用:

在线去除重复项工具: http://tools.jb51.net/code/quchong

在线文本去重复工具: http://tools.jb51.net/aideddesign/txt_quchong

Python 删除 排序数组 重复项