Class Solution

java.lang.Object
g0601_0700.s0682_baseball_game.Solution

public class Solution extends Object
682 - Baseball Game.<p>Easy</p> <p>You are keeping score for a baseball game with strange rules. The game consists of several rounds, where the scores of past rounds may affect future rounds&rsquo; scores.</p> <p>At the beginning of the game, you start with an empty record. You are given a list of strings <code>ops</code>, where <code>ops[i]</code> is the <code>i<sup>th</sup></code> operation you must apply to the record and is one of the following:</p> <ol> <li>An integer <code>x</code> - Record a new score of <code>x</code>.</li> <li><code>&quot;+&quot;</code> - Record a new score that is the sum of the previous two scores. It is guaranteed there will always be two previous scores.</li> <li><code>&quot;D&quot;</code> - Record a new score that is double the previous score. It is guaranteed there will always be a previous score.</li> <li><code>&quot;C&quot;</code> - Invalidate the previous score, removing it from the record. It is guaranteed there will always be a previous score.</li> </ol> <p>Return <em>the sum of all the scores on the record</em>.</p> <p><strong>Example 1:</strong></p> <p><strong>Input:</strong> ops = [&ldquo;5&rdquo;,&ldquo;2&rdquo;,&ldquo;C&rdquo;,&ldquo;D&rdquo;,&ldquo;+&rdquo;]</p> <p><strong>Output:</strong> 30</p> <p><strong>Explanation:</strong></p> <pre><code> &quot;5&quot; - Add 5 to the record, record is now [5]. &quot;2&quot; - Add 2 to the record, record is now [5, 2]. &quot;C&quot; - Invalidate and remove the previous score, record is now [5]. &quot;D&quot; - Add 2 \* 5 = 10 to the record, record is now [5, 10]. &quot;+&quot; - Add 5 + 10 = 15 to the record, record is now [5, 10, 15]. The total sum is 5 + 10 + 15 = 30. </code></pre> <p><strong>Example 2:</strong></p> <p><strong>Input:</strong> ops = [&ldquo;5&rdquo;,&ldquo;-2&rdquo;,&ldquo;4&rdquo;,&ldquo;C&rdquo;,&ldquo;D&rdquo;,&ldquo;9&rdquo;,&ldquo;+&rdquo;,&ldquo;+&rdquo;]</p> <p><strong>Output:</strong> 27</p> <p><strong>Explanation:</strong></p> <pre><code> &quot;5&quot; - Add 5 to the record, record is now [5]. &quot;-2&quot; - Add -2 to the record, record is now [5, -2]. &quot;4&quot; - Add 4 to the record, record is now [5, -2, 4]. &quot;C&quot; - Invalidate and remove the previous score, record is now [5, -2]. &quot;D&quot; - Add 2 \* -2 = -4 to the record, record is now [5, -2, -4]. &quot;9&quot; - Add 9 to the record, record is now [5, -2, -4, 9]. &quot;+&quot; - Add -4 + 9 = 5 to the record, record is now [5, -2, -4, 9, 5]. &quot;+&quot; - Add 9 + 5 = 14 to the record, record is now [5, -2, -4, 9, 5, 14]. The total sum is 5 + -2 + -4 + 9 + 5 + 14 = 27. </code></pre> <p><strong>Example 3:</strong></p> <p><strong>Input:</strong> ops = [&ldquo;1&rdquo;]</p> <p><strong>Output:</strong> 1</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= ops.length <= 1000</code></li> <li><code>ops[i]</code> is <code>&quot;C&quot;</code>, <code>&quot;D&quot;</code>, <code>&quot;+&quot;</code>, or a string representing an integer in the range <code>[-3 * 10<sup>4</sup>, 3 * 10<sup>4</sup>]</code>.</li> <li>For operation <code>&quot;+&quot;</code>, there will always be at least two previous scores on the record.</li> <li>For operations <code>&quot;C&quot;</code> and <code>&quot;D&quot;</code>, there will always be at least one previous score on the record.</li> </ul>
  • Constructor Details

    • Solution

      public Solution()
  • Method Details

    • calPoints

      public int calPoints(String[] ops)