LeetCode题解(0744)：寻找比目标字母大的最小字母(Python)

题目：原题链接（简单）

解法时间复杂度空间复杂度执行用时Ans 1 (Python)$O(logN)$$O(1)$136ms (69.15%)Ans 2 (Python)$O(logN)$$O(1)$136ms (69.15%)Ans 3 (Python)

LeetCode的Python执行用时随缘，只要时间复杂度没有明显差异，执行用时一般都在同一个量级，仅作参考意义。

解法一（二分查找）：

def nextGreatestLetter(self, letters: List[str], target: str) -> str: if ord(letters[-1]) <= ord(target): return letters[0] left = 0 right = len(letters) - 1 while left < right: mid = (left + right) // 2 if ord(letters[mid]) <= ord(target): left = mid + 1 else: right = mid return letters[left]

解法二（二分查找）：

def nextGreatestLetter(self, letters: List[str], target: str) -> str: left = 0 right = len(letters) - 1 while left <= right: mid = (left + right) // 2 if ord(letters[mid]) <= ord(target): left = mid + 1 else: right = mid - 1 if left == len(letters): return letters[0] else: return letters[left]