deploy: 59ce33e

Author: yanglbme

en/lc/2083/index.html

@@ -51145,9 +51145,9 @@
       <ul class="md-nav__list">
 
           <li class="md-nav__item">
-  <a href="#solution-1" class="md-nav__link">
+  <a href="#solution-1-array-or-hash-table" class="md-nav__link">
     <span class="md-ellipsis">
-      Solution 1
+      Solution 1: Array or Hash Table
     </span>
   </a>
 
@@ -82327,8 +82327,12 @@ <h2 id="description">Description</h2>
 <h2 id="solutions">Solutions</h2>
 <!-- solution:start -->
 
-<h3 id="solution-1">Solution 1</h3>
-<div class="tabbed-set tabbed-alternate" data-tabs="1:4"><input checked="checked" id="__tabbed_1_1" name="__tabbed_1" type="radio" /><input id="__tabbed_1_2" name="__tabbed_1" type="radio" /><input id="__tabbed_1_3" name="__tabbed_1" type="radio" /><input id="__tabbed_1_4" name="__tabbed_1" type="radio" /><div class="tabbed-labels"><label for="__tabbed_1_1">Python3</label><label for="__tabbed_1_2">Java</label><label for="__tabbed_1_3">C++</label><label for="__tabbed_1_4">Go</label></div>
+<h3 id="solution-1-array-or-hash-table">Solution 1: Array or Hash Table</h3>
+<p>We can use a hash table or an array $\textit{cnt}$ of length $26$ to record the occurrences of each character.</p>
+<p>Traverse the string $\textit{s}$. For each character $\textit{c}$, increment the value of $\textit{cnt}[c]$ by $1$, and then add the value of $\textit{cnt}[c]$ to the answer.</p>
+<p>Finally, return the answer.</p>
+<p>The time complexity is $O(n)$, where $n$ is the length of the string $\textit{s}$. The space complexity is $O(|\Sigma|)$, where $\Sigma$ is the character set. Here, it is lowercase English letters, so $|\Sigma|=26$.</p>
+<div class="tabbed-set tabbed-alternate" data-tabs="1:7"><input checked="checked" id="__tabbed_1_1" name="__tabbed_1" type="radio" /><input id="__tabbed_1_2" name="__tabbed_1" type="radio" /><input id="__tabbed_1_3" name="__tabbed_1" type="radio" /><input id="__tabbed_1_4" name="__tabbed_1" type="radio" /><input id="__tabbed_1_5" name="__tabbed_1" type="radio" /><input id="__tabbed_1_6" name="__tabbed_1" type="radio" /><input id="__tabbed_1_7" name="__tabbed_1" type="radio" /><div class="tabbed-labels"><label for="__tabbed_1_1">Python3</label><label for="__tabbed_1_2">Java</label><label for="__tabbed_1_3">C++</label><label for="__tabbed_1_4">Go</label><label for="__tabbed_1_5">TypeScript</label><label for="__tabbed_1_6">Rust</label><label for="__tabbed_1_7">JavaScript</label></div>
 <div class="tabbed-content">
 <div class="tabbed-block">
 <div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span></span><span class="normal">1</span>
@@ -82358,16 +82362,12 @@ <h3 id="solution-1">Solution 1</h3>
 <span class="normal"> 7</span>
 <span class="normal"> 8</span>
 <span class="normal"> 9</span>
-<span class="normal">10</span>
-<span class="normal">11</span>
-<span class="normal">12</span></pre></div></td><td class="code"><div><pre><span></span><code><span class="kd">class</span> <span class="nc">Solution</span><span class="w"> </span><span class="p">{</span>
+<span class="normal">10</span></pre></div></td><td class="code"><div><pre><span></span><code><span class="kd">class</span> <span class="nc">Solution</span><span class="w"> </span><span class="p">{</span>
 <span class="w">    </span><span class="kd">public</span><span class="w"> </span><span class="kt">long</span><span class="w"> </span><span class="nf">numberOfSubstrings</span><span class="p">(</span><span class="n">String</span><span class="w"> </span><span class="n">s</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
 <span class="w">        </span><span class="kt">int</span><span class="o">[]</span><span class="w"> </span><span class="n">cnt</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="k">new</span><span class="w"> </span><span class="kt">int</span><span class="o">[</span><span class="mi">26</span><span class="o">]</span><span class="p">;</span>
 <span class="w">        </span><span class="kt">long</span><span class="w"> </span><span class="n">ans</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span>
-<span class="w">        </span><span class="k">for</span><span class="w"> </span><span class="p">(</span><span class="kt">int</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0</span><span class="p">;</span><span class="w"> </span><span class="n">i</span><span class="w"> </span><span class="o">&lt;</span><span class="w"> </span><span class="n">s</span><span class="p">.</span><span class="na">length</span><span class="p">();</span><span class="w"> </span><span class="o">++</span><span class="n">i</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
-<span class="w">            </span><span class="kt">int</span><span class="w"> </span><span class="n">j</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">s</span><span class="p">.</span><span class="na">charAt</span><span class="p">(</span><span class="n">i</span><span class="p">)</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="sc">&#39;a&#39;</span><span class="p">;</span>
-<span class="w">            </span><span class="o">++</span><span class="n">cnt</span><span class="o">[</span><span class="n">j</span><span class="o">]</span><span class="p">;</span>
-<span class="w">            </span><span class="n">ans</span><span class="w"> </span><span class="o">+=</span><span class="w"> </span><span class="n">cnt</span><span class="o">[</span><span class="n">j</span><span class="o">]</span><span class="p">;</span>
+<span class="w">        </span><span class="k">for</span><span class="w"> </span><span class="p">(</span><span class="kt">char</span><span class="w"> </span><span class="n">c</span><span class="w"> </span><span class="p">:</span><span class="w"> </span><span class="n">s</span><span class="p">.</span><span class="na">toCharArray</span><span class="p">())</span><span class="w"> </span><span class="p">{</span>
+<span class="w">            </span><span class="n">ans</span><span class="w"> </span><span class="o">+=</span><span class="w"> </span><span class="o">++</span><span class="n">cnt</span><span class="o">[</span><span class="n">c</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="sc">&#39;a&#39;</span><span class="o">]</span><span class="p">;</span>
 <span class="w">        </span><span class="p">}</span>
 <span class="w">        </span><span class="k">return</span><span class="w"> </span><span class="n">ans</span><span class="p">;</span>
 <span class="w">    </span><span class="p">}</span>
@@ -82418,6 +82418,80 @@ <h3 id="solution-1">Solution 1</h3>
 <span class="p">}</span>
 </code></pre></div></td></tr></table></div>
 </div>
+<div class="tabbed-block">
+<div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span></span><span class="normal">1</span>
+<span class="normal">2</span>
+<span class="normal">3</span>
+<span class="normal">4</span>
+<span class="normal">5</span>
+<span class="normal">6</span>
+<span class="normal">7</span>
+<span class="normal">8</span>
+<span class="normal">9</span></pre></div></td><td class="code"><div><pre><span></span><code><span class="kd">function</span><span class="w"> </span><span class="nx">numberOfSubstrings</span><span class="p">(</span><span class="nx">s</span><span class="o">:</span><span class="w"> </span><span class="kt">string</span><span class="p">)</span><span class="o">:</span><span class="w"> </span><span class="kt">number</span><span class="w"> </span><span class="p">{</span>
+<span class="w">    </span><span class="kd">const</span><span class="w"> </span><span class="nx">cnt</span><span class="o">:</span><span class="w"> </span><span class="kt">Record</span><span class="o">&lt;</span><span class="kt">string</span><span class="p">,</span><span class="w"> </span><span class="kt">number</span><span class="o">&gt;</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">{};</span>
+<span class="w">    </span><span class="kd">let</span><span class="w"> </span><span class="nx">ans</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mf">0</span><span class="p">;</span>
+<span class="w">    </span><span class="k">for</span><span class="w"> </span><span class="p">(</span><span class="kd">const</span><span class="w"> </span><span class="nx">c</span><span class="w"> </span><span class="k">of</span><span class="w"> </span><span class="nx">s</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
+<span class="w">        </span><span class="nx">cnt</span><span class="p">[</span><span class="nx">c</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">(</span><span class="nx">cnt</span><span class="p">[</span><span class="nx">c</span><span class="p">]</span><span class="w"> </span><span class="o">||</span><span class="w"> </span><span class="mf">0</span><span class="p">)</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mf">1</span><span class="p">;</span>
+<span class="w">        </span><span class="nx">ans</span><span class="w"> </span><span class="o">+=</span><span class="w"> </span><span class="nx">cnt</span><span class="p">[</span><span class="nx">c</span><span class="p">];</span>
+<span class="w">    </span><span class="p">}</span>
+<span class="w">    </span><span class="k">return</span><span class="w"> </span><span class="nx">ans</span><span class="p">;</span>
+<span class="p">}</span>
+</code></pre></div></td></tr></table></div>
+</div>
+<div class="tabbed-block">
+<div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span></span><span class="normal"> 1</span>
+<span class="normal"> 2</span>
+<span class="normal"> 3</span>
+<span class="normal"> 4</span>
+<span class="normal"> 5</span>
+<span class="normal"> 6</span>
+<span class="normal"> 7</span>
+<span class="normal"> 8</span>
+<span class="normal"> 9</span>
+<span class="normal">10</span>
+<span class="normal">11</span>
+<span class="normal">12</span></pre></div></td><td class="code"><div><pre><span></span><code><span class="k">impl</span><span class="w"> </span><span class="n">Solution</span><span class="w"> </span><span class="p">{</span>
+<span class="w">    </span><span class="k">pub</span><span class="w"> </span><span class="k">fn</span><span class="w"> </span><span class="nf">number_of_substrings</span><span class="p">(</span><span class="n">s</span><span class="p">:</span><span class="w"> </span><span class="nb">String</span><span class="p">)</span><span class="w"> </span><span class="p">-&gt;</span><span class="w"> </span><span class="kt">i64</span><span class="w"> </span><span class="p">{</span>
+<span class="w">        </span><span class="kd">let</span><span class="w"> </span><span class="k">mut</span><span class="w"> </span><span class="n">cnt</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">[</span><span class="mi">0</span><span class="p">;</span><span class="w"> </span><span class="mi">26</span><span class="p">];</span>
+<span class="w">        </span><span class="kd">let</span><span class="w"> </span><span class="k">mut</span><span class="w"> </span><span class="n">ans</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">0_</span><span class="k">i64</span><span class="p">;</span>
+<span class="w">        </span><span class="k">for</span><span class="w"> </span><span class="n">c</span><span class="w"> </span><span class="k">in</span><span class="w"> </span><span class="n">s</span><span class="p">.</span><span class="n">chars</span><span class="p">()</span><span class="w"> </span><span class="p">{</span>
+<span class="w">            </span><span class="kd">let</span><span class="w"> </span><span class="n">idx</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">(</span><span class="n">c</span><span class="w"> </span><span class="k">as</span><span class="w"> </span><span class="kt">u8</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="sc">b&#39;a&#39;</span><span class="p">)</span><span class="w"> </span><span class="k">as</span><span class="w"> </span><span class="kt">usize</span><span class="p">;</span>
+<span class="w">            </span><span class="n">cnt</span><span class="p">[</span><span class="n">idx</span><span class="p">]</span><span class="w"> </span><span class="o">+=</span><span class="w"> </span><span class="mi">1</span><span class="p">;</span>
+<span class="w">            </span><span class="n">ans</span><span class="w"> </span><span class="o">+=</span><span class="w"> </span><span class="n">cnt</span><span class="p">[</span><span class="n">idx</span><span class="p">];</span>
+<span class="w">        </span><span class="p">}</span>
+<span class="w">        </span><span class="n">ans</span>
+<span class="w">    </span><span class="p">}</span>
+<span class="p">}</span>
+</code></pre></div></td></tr></table></div>
+</div>
+<div class="tabbed-block">
+<div class="highlight"><table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre><span></span><span class="normal"> 1</span>
+<span class="normal"> 2</span>
+<span class="normal"> 3</span>
+<span class="normal"> 4</span>
+<span class="normal"> 5</span>
+<span class="normal"> 6</span>
+<span class="normal"> 7</span>
+<span class="normal"> 8</span>
+<span class="normal"> 9</span>
+<span class="normal">10</span>
+<span class="normal">11</span>
+<span class="normal">12</span>
+<span class="normal">13</span></pre></div></td><td class="code"><div><pre><span></span><code><span class="cm">/**</span>
+<span class="cm"> * @param {string} s</span>
+<span class="cm"> * @return {number}</span>
+<span class="cm"> */</span>
+<span class="kd">var</span><span class="w"> </span><span class="nx">numberOfSubstrings</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="kd">function</span><span class="w"> </span><span class="p">(</span><span class="nx">s</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
+<span class="w">    </span><span class="kd">const</span><span class="w"> </span><span class="nx">cnt</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">{};</span>
+<span class="w">    </span><span class="kd">let</span><span class="w"> </span><span class="nx">ans</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mf">0</span><span class="p">;</span>
+<span class="w">    </span><span class="k">for</span><span class="w"> </span><span class="p">(</span><span class="kd">const</span><span class="w"> </span><span class="nx">c</span><span class="w"> </span><span class="k">of</span><span class="w"> </span><span class="nx">s</span><span class="p">)</span><span class="w"> </span><span class="p">{</span>
+<span class="w">        </span><span class="nx">cnt</span><span class="p">[</span><span class="nx">c</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">(</span><span class="nx">cnt</span><span class="p">[</span><span class="nx">c</span><span class="p">]</span><span class="w"> </span><span class="o">||</span><span class="w"> </span><span class="mf">0</span><span class="p">)</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="mf">1</span><span class="p">;</span>
+<span class="w">        </span><span class="nx">ans</span><span class="w"> </span><span class="o">+=</span><span class="w"> </span><span class="nx">cnt</span><span class="p">[</span><span class="nx">c</span><span class="p">];</span>
+<span class="w">    </span><span class="p">}</span>
+<span class="w">    </span><span class="k">return</span><span class="w"> </span><span class="nx">ans</span><span class="p">;</span>
+<span class="p">};</span>
+</code></pre></div></td></tr></table></div>
+</div>
 </div>
 </div>
 <!-- solution:end -->