PHP删除排序数组中的重复项,Python实现删除排序数组中重复项的两种方法示例

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：

希望本文所述对大家Python程序设计有所帮助。