What is the pattern of this problem?

This problem involves manipulating an array of strings and converting them into numeric or length values for comparison, fitting the 'Array plus String' pattern.

How do I handle strings with both letters and digits?

For strings that contain both letters and digits, treat their value as the length of the string.

What should I do for strings that consist only of digits?

For digit-only strings, convert them into integers to get their numeric value.

What is the time complexity of this problem?

The time complexity is O(n), where n is the number of strings in the array.

How can I optimize my solution for large inputs?

You can optimize by avoiding redundant calculations and keeping track of the maximum value in a single pass through the array.

#2496

Easy

auto_awesome数组·string

LeetCode 题解工作台

数组中字符串的最大值

一个由字母和数字组成的字符串的值定义如下：如果字符串只包含数字，那么值为该字符串在 10 进制下的所表示的数字。否则，值为字符串的长度。给你一个字符串数组 strs ，每个字符串都只由字母和数字组成，请你返回 strs 中字符串的最大值。示例 1：输入： strs = ["…

数组字符串

题目描述

一个由字母和数字组成的字符串的值定义如下：

如果字符串只包含数字，那么值为该字符串在 10 进制下的所表示的数字。
否则，值为字符串的长度。

给你一个字符串数组 strs ，每个字符串都只由字母和数字组成，请你返回 strs 中字符串的 最大值 。

示例 1：

输入：strs = ["alic3","bob","3","4","00000"]
输出：5
解释：
- "alic3" 包含字母和数字，所以值为长度 5 。
- "bob" 只包含字母，所以值为长度 3 。
- "3" 只包含数字，所以值为 3 。
- "4" 只包含数字，所以值为 4 。
- "00000" 只包含数字，所以值为 0 。
所以最大的值为 5 ，是字符串 "alic3" 的值。

示例 2：

输入：strs = ["1","01","001","0001"]
输出：1
解释：
数组中所有字符串的值都是 1 ，所以我们返回 1 。

提示：

1 <= strs.length <= 100
1 <= strs[i].length <= 9
strs[i] 只包含小写英文字母和数字。

lightbulb

解题思路

方法一：模拟

我们定义一个函数 $f(s)$ ，用于计算字符串 $s$ 的值。如果 $s$ 只包含数字，那么 $f(s)$ 就是 $s$ 在十进制下的值；否则 $f(s)$ 就是 $s$ 的长度。

答案为 $\max\limits_{s \in \textit{strs}} f(s)$ 。

时间复杂度 $O(n)$ ，其中 $n$ 是数组 $strs$ 的长度。空间复杂度 $O(1)$ 。

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class Solution:
    def maximumValue(self, strs: List[str]) -> int:
        def f(s: str) -> int:
            return int(s) if all(c.isdigit() for c in s) else len(s)

        return max(f(s) for s in strs)

speed

复杂度分析

指标	值
时间	complexity is O(n), where n is the number of strings in the array, and space complexity is O(1) since only a few variables are used to track the maximum value during iteration.
空间	Depends on the final approach

psychology

面试官常问的追问

外企场景

question_mark
Tests understanding of string manipulation and number conversion.
question_mark
Checks if the candidate can correctly handle different data types (strings and integers).
question_mark
Assesses problem-solving skills in array traversal and maximum value tracking.

warning

常见陷阱

外企场景

error
Failing to convert digit-only strings into integers, leading to incorrect comparisons.
error
Not properly handling strings that consist solely of letters (should rely on length).
error
Confusing the value of strings that contain both letters and digits, which requires taking their length.

swap_horiz

进阶变体

外企场景

arrow_right_alt
Consider additional edge cases with strings of varying lengths and characters.
arrow_right_alt
Handle cases where multiple strings have the same value, ensuring the correct maximum is returned.
arrow_right_alt
Explore performance optimizations when dealing with large input sizes, such as avoiding redundant calculations.

help

常见问题

外企场景

继续练习

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