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@@ -239,20 +239,20 @@
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<p>这种方法有点类似<a href="http://baidu.physton.com/?q=dijkstra" target="_blank" rel="noopener" title="这都不会?">Dijstra</a>,就是每次从所有<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mi>v</mi><mi>i</mi><mi>s</mi></mrow><annotation encoding="application/x-tex">vis</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.65952em;vertical-align:0em;"></span><span class="mord mathdefault" style="margin-right:0.03588em;">v</span><span class="mord mathdefault">i</span><span class="mord mathdefault">s</span></span></span></span>过的点遍历能达到的边,从其中选择一条最小的,加入生成树。</p>
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<hr />
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<p>假设我们有这么一张图:<br />
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-<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img src="https://img-blog.csdnimg.cn/20200103203601629.png" alt="" /></a></p>
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+<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img data-src="https://img-blog.csdnimg.cn/20200103203601629.png" alt="" /></a></p>
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<p>就从0号点开始吧:<br />
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<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><br />
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-<img src="https://img-blog.csdnimg.cn/20200103204749157.png" alt="在这里插入图片描述" /></a></p>
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+<img data-src="https://img-blog.csdnimg.cn/20200103204749157.png" alt="在这里插入图片描述" /></a></p>
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<p>找到从<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>0</mn></mrow><annotation encoding="application/x-tex">0</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.64444em;vertical-align:0em;"></span><span class="mord">0</span></span></span></span>出发的最小的边:<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mo stretchy="false">[</mo><mn>0</mn><mo separator="true">,</mo><mn>2</mn><mo stretchy="false">]</mo></mrow><annotation encoding="application/x-tex">[0,2]</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mopen">[</span><span class="mord">0</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.16666666666666666em;"></span><span class="mord">2</span><span class="mclose">]</span></span></span></span>,边权为<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>3</mn></mrow><annotation encoding="application/x-tex">3</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.64444em;vertical-align:0em;"></span><span class="mord">3</span></span></span></span>,那么对<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>2</mn></mrow><annotation encoding="application/x-tex">2</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.64444em;vertical-align:0em;"></span><span class="mord">2</span></span></span></span>号点进行标记。<br />
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-<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img src="https://img-blog.csdnimg.cn/20200103205741495.png" alt="" /></a></p>
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+<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img data-src="https://img-blog.csdnimg.cn/20200103205741495.png" alt="" /></a></p>
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<p>然后从<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>0</mn></mrow><annotation encoding="application/x-tex">0</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.64444em;vertical-align:0em;"></span><span class="mord">0</span></span></span></span>号和<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>2</mn></mrow><annotation encoding="application/x-tex">2</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.64444em;vertical-align:0em;"></span><span class="mord">2</span></span></span></span>号节点继续找,发现最小的是<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mo stretchy="false">[</mo><mn>2</mn><mo separator="true">,</mo><mn>4</mn><mo stretchy="false">]</mo></mrow><annotation encoding="application/x-tex">[2,4]</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mopen">[</span><span class="mord">2</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.16666666666666666em;"></span><span class="mord">4</span><span class="mclose">]</span></span></span></span>边,那么就标记<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>4</mn></mrow><annotation encoding="application/x-tex">4</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.64444em;vertical-align:0em;"></span><span class="mord">4</span></span></span></span>号节点。<br />
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-<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img src="https://img-blog.csdnimg.cn/20200103210306831.png" alt="在这里插入图片描述" /></a></p>
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+<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img data-src="https://img-blog.csdnimg.cn/20200103210306831.png" alt="在这里插入图片描述" /></a></p>
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<p>然后是<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mo stretchy="false">[</mo><mn>4</mn><mo separator="true">,</mo><mn>1</mn><mo stretchy="false">]</mo></mrow><annotation encoding="application/x-tex">[4,1]</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mopen">[</span><span class="mord">4</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.16666666666666666em;"></span><span class="mord">1</span><span class="mclose">]</span></span></span></span>,<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>1</mn></mrow><annotation encoding="application/x-tex">1</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.64444em;vertical-align:0em;"></span><span class="mord">1</span></span></span></span>号。<br />
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-<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img src="https://img-blog.csdnimg.cn/20200103210445854.png" alt="在这里插入图片描述" /></a></p>
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+<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img data-src="https://img-blog.csdnimg.cn/20200103210445854.png" alt="在这里插入图片描述" /></a></p>
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<p>以此类推,最后就生成出来了这样一个图:</p>
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-<p><a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img src="https://img-blog.csdnimg.cn/20200103210621487.png" alt="在这里插入图片描述" /></a></p>
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+<p><a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img data-src="https://img-blog.csdnimg.cn/20200103210621487.png" alt="在这里插入图片描述" /></a></p>
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<p>把没有标记的边删掉,就是最小生成树。<br />
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-<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img src="https://img-blog.csdnimg.cn/20200103210727778.png" alt="" /></a></p>
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+<a href="https://csacademy.com/app/graph_editor" target="_blank" rel="noopener" title="点击查看生成工具"><img data-src="https://img-blog.csdnimg.cn/20200103210727778.png" alt="" /></a></p>
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<p>这就是prim算法 <s>,代码我不会写</s>在后面。</p>
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<h3 id="生成方式二kruskal"><a class="markdownIt-Anchor" href="#生成方式二kruskal"></a> 生成方式二:kruskal</h3>
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<p>这个算法本质上就是把所有边按照边权排序,然后直接<s>爆炸</s>按顺序判断要不要加进生成树里。<br />
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@@ -260,15 +260,15 @@ kruskal算法使用了一种极速闪电致命又自杀的东西:并查集。<
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<a href="https://schtonn.github.io/post/union-find-set">他有多快呢?</a></p>
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<hr />
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<p>好了我们在建一个图模拟一下吧<br />
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-<img src="https://img-blog.csdnimg.cn/20200103215213917.png" alt="在这里插入图片描述" /></p>
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+<img data-src="https://img-blog.csdnimg.cn/20200103215213917.png" alt="在这里插入图片描述" /></p>
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<p>先给边排序。最小的是<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mo stretchy="false">[</mo><mn>2</mn><mo separator="true">,</mo><mn>3</mn><mo stretchy="false">]</mo></mrow><annotation encoding="application/x-tex">[2,3]</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mopen">[</span><span class="mord">2</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.16666666666666666em;"></span><span class="mord">3</span><span class="mclose">]</span></span></span></span>,把他拿出来,判断一下。怎么判断呢?首先访问一下并查集看一看,这个边连接的两个点在不在同一个集合内,不在的话就把这条边加入生成树,然后把两个点合并。否则忽略这一条变,继续。这一条边符合要求,加进并查集里,现在<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>2</mn><mo separator="true">,</mo><mn>3</mn></mrow><annotation encoding="application/x-tex">{2,3}</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.8388800000000001em;vertical-align:-0.19444em;"></span><span class="mord"><span class="mord">2</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.16666666666666666em;"></span><span class="mord">3</span></span></span></span></span>是一个集合,剩下都是独立的。</p>
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-<p><img src="https://img-blog.csdnimg.cn/20200103215304212.png" alt="在这里插入图片描述" /><br />
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+<p><img data-src="https://img-blog.csdnimg.cn/20200103215304212.png" alt="在这里插入图片描述" /><br />
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现在最小的有<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mo stretchy="false">[</mo><mn>1</mn><mo separator="true">,</mo><mn>4</mn><mo stretchy="false">]</mo></mrow><annotation encoding="application/x-tex">[1,4]</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mopen">[</span><span class="mord">1</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.16666666666666666em;"></span><span class="mord">4</span><span class="mclose">]</span></span></span></span>和<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mo stretchy="false">[</mo><mn>4</mn><mo separator="true">,</mo><mn>5</mn><mo stretchy="false">]</mo></mrow><annotation encoding="application/x-tex">[4,5]</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mopen">[</span><span class="mord">4</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.16666666666666666em;"></span><span class="mord">5</span><span class="mclose">]</span></span></span></span>,我们都判断一下,都可以。<br />
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-<img src="https://img-blog.csdnimg.cn/20200103215356204.png" alt="在这里插入图片描述" /></p>
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+<img data-src="https://img-blog.csdnimg.cn/20200103215356204.png" alt="在这里插入图片描述" /></p>
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<p>然后就是<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mo stretchy="false">[</mo><mn>0</mn><mo separator="true">,</mo><mn>4</mn><mo stretchy="false">]</mo></mrow><annotation encoding="application/x-tex">[0,4]</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mopen">[</span><span class="mord">0</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.16666666666666666em;"></span><span class="mord">4</span><span class="mclose">]</span></span></span></span>和<span class="katex"><span class="katex-mathml"><math><semantics><mrow><mo stretchy="false">[</mo><mn>2</mn><mo separator="true">,</mo><mn>4</mn><mo stretchy="false">]</mo></mrow><annotation encoding="application/x-tex">[2,4]</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mopen">[</span><span class="mord">2</span><span class="mpunct">,</span><span class="mspace" style="margin-right:0.16666666666666666em;"></span><span class="mord">4</span><span class="mclose">]</span></span></span></span>,依然都是可以的。<br />
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-<img src="https://img-blog.csdnimg.cn/20200103215507942.png" alt="在这里插入图片描述" /><br />
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+<img data-src="https://img-blog.csdnimg.cn/20200103215507942.png" alt="在这里插入图片描述" /><br />
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这样,一颗活灵活现的生成树就出现了。<br />
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-<img src="https://img-blog.csdnimg.cn/20200103215600881.png" alt="" /></p>
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+<img data-src="https://img-blog.csdnimg.cn/20200103215600881.png" alt="" /></p>
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<p>好了!</p>
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<h3 id="代码luogup3366"><a class="markdownIt-Anchor" href="#代码luogup3366"></a> 代码(<a href="https://www.luogu.com.cn/problem/P3366" target="_blank" rel="noopener">luoguP3366</a>)</h3>
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<p>kruskal的代码又短又易于理解,甚至可以直接用数组存边,所以他非常好写,推荐。</p>
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