DEV Community

Abhishek Chaudhary
Abhishek Chaudhary

Posted on

1

Set Mismatch

You have a set of integers s, which originally contains all the numbers from 1 to n. Unfortunately, due to some error, one of the numbers in s got duplicated to another number in the set, which results in repetition of one number and loss of another number.

You are given an integer array nums representing the data status of this set after the error.

Find the number that occurs twice and the number that is missing and return them in the form of an array.

Example 1:

Input: nums = [1,2,2,4]
Output: [2,3]

Example 2:

Input: nums = [1,1]
Output: [1,2]

Constraints:

  • 2 <= nums.length <= 104
  • 1 <= nums[i] <= 104

SOLUTION:

class Solution:
    def findErrorNums(self, nums: List[int]) -> List[int]:
        ctr = set()
        n = len(nums)
        for i in range(1, n + 1):
            ctr.add(i)
        for num in nums:
            if num in ctr:
                ctr.remove(num)
            else:
                dup = num
        return [dup, list(ctr)[0]]
Enter fullscreen mode Exit fullscreen mode

AWS Q Developer image

Your AI Code Assistant

Ask anything about your entire project, code and get answers and even architecture diagrams. Built to handle large projects, Amazon Q Developer works alongside you from idea to production code.

Start free in your IDE

Top comments (0)

A Workflow Copilot. Tailored to You.

Pieces.app image

Our desktop app, with its intelligent copilot, streamlines coding by generating snippets, extracting code from screenshots, and accelerating problem-solving.

Read the docs

👋 Kindness is contagious

Please leave a ❤️ or a friendly comment on this post if you found it helpful!

Okay