leetcode-problemset/leetcode-cn/problem (English)/网格图中机器人回家的最小代价(English) [minimum-cost-homecoming-of-a-robot-in-a-grid].html

<p>There is an <code>m x n</code> grid, where <code>(0, 0)</code> is the top-left cell and <code>(m - 1, n - 1)</code> is the bottom-right cell. You are given an integer array <code>startPos</code> where <code>startPos = [start<sub>row</sub>, start<sub>col</sub>]</code> indicates that <strong>initially</strong>, a <strong>robot</strong> is at the cell <code>(start<sub>row</sub>, start<sub>col</sub>)</code>. You are also given an integer array <code>homePos</code> where <code>homePos = [home<sub>row</sub>, home<sub>col</sub>]</code> indicates that its <strong>home</strong> is at the cell <code>(home<sub>row</sub>, home<sub>col</sub>)</code>.</p>

<p>The robot needs to go to its home. It can move one cell in four directions: <strong>left</strong>, <strong>right</strong>, <strong>up</strong>, or <strong>down</strong>, and it can not move outside the boundary. Every move incurs some cost. You are further given two <strong>0-indexed</strong> integer arrays: <code>rowCosts</code> of length <code>m</code> and <code>colCosts</code> of length <code>n</code>.</p>

<ul>
	<li>If the robot moves <strong>up</strong> or <strong>down</strong> into a cell whose <strong>row</strong> is <code>r</code>, then this move costs <code>rowCosts[r]</code>.</li>
	<li>If the robot moves <strong>left</strong> or <strong>right</strong> into a cell whose <strong>column</strong> is <code>c</code>, then this move costs <code>colCosts[c]</code>.</li>
</ul>

<p>Return <em>the <strong>minimum total cost</strong> for this robot to return home</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/10/11/eg-1.png" style="width: 282px; height: 217px;" />
<pre>
<strong>Input:</strong> startPos = [1, 0], homePos = [2, 3], rowCosts = [5, 4, 3], colCosts = [8, 2, 6, 7]
<strong>Output:</strong> 18
<strong>Explanation:</strong> One optimal path is that:
Starting from (1, 0)
-&gt; It goes down to (<u><strong>2</strong></u>, 0). This move costs rowCosts[2] = 3.
-&gt; It goes right to (2, <u><strong>1</strong></u>). This move costs colCosts[1] = 2.
-&gt; It goes right to (2, <u><strong>2</strong></u>). This move costs colCosts[2] = 6.
-&gt; It goes right to (2, <u><strong>3</strong></u>). This move costs colCosts[3] = 7.
The total cost is 3 + 2 + 6 + 7 = 18</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> startPos = [0, 0], homePos = [0, 0], rowCosts = [5], colCosts = [26]
<strong>Output:</strong> 0
<strong>Explanation:</strong> The robot is already at its home. Since no moves occur, the total cost is 0.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>m == rowCosts.length</code></li>
	<li><code>n == colCosts.length</code></li>
	<li><code>1 &lt;= m, n &lt;= 10<sup>5</sup></code></li>
	<li><code>0 &lt;= rowCosts[r], colCosts[c] &lt;= 10<sup>4</sup></code></li>
	<li><code>startPos.length == 2</code></li>
	<li><code>homePos.length == 2</code></li>
	<li><code>0 &lt;= start<sub>row</sub>, home<sub>row</sub> &lt; m</code></li>
	<li><code>0 &lt;= start<sub>col</sub>, home<sub>col</sub> &lt; n</code></li>
</ul>