Python - Algorithm #34

Python Algorithm

LeetCode

1374. Generate a String With Characters That Have Odd Counts

• Given an integer n, return a string with n characters such that each character in such string occurs an odd number of times.
• The returned string must contain only lowercase English letters. If there are multiples valid strings, return any of them.
• Constraints
  • 1 ≤ n ≤ 500

class Solution:
    def generateTheString(self, n: int) -> str:
        # n이 홀수일 때와 짝수일 때를 구분 지어 볼 것
        if n % 2 == 1:
            return "a" * n
        else:
            return "a" * (n-1) + "b"

class Solution:
    def generateTheString(self, n: int) -> str:
        for i in range(n):
            if n % 2 == 0:
                return "a" * (n-1) + "b"
            else:
                return "a" * n

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2016. Maximum Difference Between Increasing Elements

• Given a 0-indexed integer array [nums] of size n, find the maximum difference between nums[i] and nums[j] (i.e., nums[j] - nums[i]), such that 0 <= i < j < n and nums[i] < nums[j].
• Return the maximum difference. If no such i and j exists, return -1.
• Constraints
  • n == nums.length
  • 2 ≤ n ≤ 1000
  • 1 ≤ nums[i] ≤ 10⁹

class Solution:
    def maximumDifference(self, nums: List[int]) -> int:
        # 2중 for문 사용
        answer = -1
        for i in range(len(nums)):
            for j in range(i+1, len(nums)):
                # nums[i] < nums[j]일 때, max diff를 answer로 지정
                if nums[j] > nums[i]:
                    answer = max(answer, nums[j] - nums[i])
        return answer

class Solution:
    def maximumDifference(self, nums: List[int]) -> int:
        min_num = float("inf")
        answer = -1
        for num in nums:
            if num > min_num:
                answer = max(answer, num - min_num)
            else:
                min_num = num
        return answer

class Solution:
    def maximumDifference(self, nums: List[int]) -> int:
        answer = -1
        for i in range(len(nums)):
            for j in range(i+1, len(nums)):
                if nums[i] < nums[j]:
                    answer = max(answer, (nums[j] - nums[i]))
        return answer

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https://leetcode.com/problems/generate-a-string-with-characters-that-have-odd-counts/

https://leetcode.com/problems/maximum-difference-between-increasing-elements/