71 lines
1.7 KiB
Markdown
71 lines
1.7 KiB
Markdown
# [3516] Find Closest Person
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## 題目資訊
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- **難度**: Easy
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- **標籤**: Math
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- **題目連結**: [LeetCode](https://leetcode.com/problems/find-closest-person/)
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- **練習日期**: 2025-09-04
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## 題目描述
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You are given three integers `x`, `y`, and `z`, representing the positions of three people on a number line:
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`x` is the position of Person 1.
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`y` is the position of Person 2.
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`z` is the position of Person 3, who does **not** move.
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Both Person 1 and Person 2 move toward Person 3 at the same speed.
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Determine which person reaches Person 3 first:
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Return 1 if Person 1 arrives first.
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Return 2 if Person 2 arrives first.
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Return 0 if both arrive at the same time.
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Return the result accordingly.
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## 解題思路
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### 初步分析
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- 這題主要考察什麼概念？
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距離計算和比較。使用絕對值計算兩點間距離
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- 有什麼關鍵限制條件？
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比較兩個距離的大小關係
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- 預期時間/空間複雜度？
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時間 O(1)，空間 O(1) - 只需要常數時間的計算
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### 解法概述
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**解法**:
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- 思路：
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分別計算 Person 1 和 Person 2 到 Person 3 的距離，直接比較大小
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- 時間複雜度：O(1)
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- 空間複雜度：O(1)
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## 測試案例
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### 範例輸入輸出
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```
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Input: x = 2, y = 7, z = 4
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Output: 1
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Explanation:
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- Person 1 is at position 2 and can reach Person 3 (at position 4) in 2 steps.
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- Person 2 is at position 7 and can reach Person 3 in 3 steps.
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Since Person 1 reaches Person 3 first, the output is 1.
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```
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### 邊界情況
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`1 <= x, y, z <= 100`
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## 學習筆記
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### 今天學到什麼？
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- 稍微練習了一下go func
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### 遇到的困難
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- 無
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### 改善方向
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- 無
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### 相關題目
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---
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**總結**: 今天這題考弱智?
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