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<div class="example" id="arrays">
<h2><a href="./">Go by Example</a>: Arrays</h2>
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<p>Em Go, um <em>array</em> é uma sequência numerada de elementos
de um tamanho específico. Tipicamente, <a href="slices">slices</a> são
muito mais comuns; arrays são úteis em alguns cenários
específicos.</p>
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<a target="_blank" href="https://go.dev/play/p/6x5yvAy8AT6"><img title="Executar código em nova aba" src="play.png" class="run" /></a><img title="Copiar código" src="clipboard.png" class="copy" />
<pre class="chroma"><span class="kn">package</span> <span class="nx">main</span>
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<pre class="chroma"><span class="kn">import</span> <span class="s">&#34;fmt&#34;</span>
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<pre class="chroma"><span class="kd">func</span> <span class="nf">main</span><span class="p">()</span> <span class="p">{</span>
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<p>Aqui é criado um array <code>a</code> com capacidade de armazenar
exatamente 5 inteiros. O tipo de elemento que ele irá
armazenar (int) e seu tamanho (5) são partes do tipo do array.
Neste caso, o array tem valores padrão zero.</p>
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<pre class="chroma">
<span class="kd">var</span> <span class="nx">a</span> <span class="p">[</span><span class="mi">5</span><span class="p">]</span><span class="kt">int</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="s">&#34;vazio:&#34;</span><span class="p">,</span> <span class="nx">a</span><span class="p">)</span>
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<p>É possível alterar o valor de um índice do array
utilizando a sintaxe <code>array[índice] = valor</code>,
bem como selecionar um valor com <code>array[índice]</code>.</p>
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<pre class="chroma">
<span class="nx">a</span><span class="p">[</span><span class="mi">4</span><span class="p">]</span> <span class="p">=</span> <span class="mi">100</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="s">&#34;índice 4 alterado:&#34;</span><span class="p">,</span> <span class="nx">a</span><span class="p">)</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="s">&#34;valor índice 4:&#34;</span><span class="p">,</span> <span class="nx">a</span><span class="p">[</span><span class="mi">4</span><span class="p">])</span>
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<p>A função nativa <code>len</code> retorna o tamanho de um array.</p>
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<pre class="chroma">
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="s">&#34;len:&#34;</span><span class="p">,</span> <span class="nb">len</span><span class="p">(</span><span class="nx">a</span><span class="p">))</span>
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<p>Para declarar a inicializar um array em uma linha,
é possível usar esta sintaxe.</p>
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<pre class="chroma">
<span class="nx">b</span> <span class="o">:=</span> <span class="p">[</span><span class="mi">5</span><span class="p">]</span><span class="kt">int</span><span class="p">{</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">5</span><span class="p">}</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="s">&#34;array inicializado:&#34;</span><span class="p">,</span> <span class="nx">b</span><span class="p">)</span>
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<p>Arrays, via de regra são unidimensionais, mas é possível
compor tipos para formar arrays multidimensionais.</p>
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<pre class="chroma">
<span class="kd">var</span> <span class="nx">twoD</span> <span class="p">[</span><span class="mi">2</span><span class="p">][</span><span class="mi">3</span><span class="p">]</span><span class="kt">int</span>
<span class="k">for</span> <span class="nx">i</span> <span class="o">:=</span> <span class="mi">0</span><span class="p">;</span> <span class="nx">i</span> <span class="p">&lt;</span> <span class="mi">2</span><span class="p">;</span> <span class="nx">i</span><span class="o">++</span> <span class="p">{</span>
<span class="k">for</span> <span class="nx">j</span> <span class="o">:=</span> <span class="mi">0</span><span class="p">;</span> <span class="nx">j</span> <span class="p">&lt;</span> <span class="mi">3</span><span class="p">;</span> <span class="nx">j</span><span class="o">++</span> <span class="p">{</span>
<span class="nx">twoD</span><span class="p">[</span><span class="nx">i</span><span class="p">][</span><span class="nx">j</span><span class="p">]</span> <span class="p">=</span> <span class="nx">i</span> <span class="o">+</span> <span class="nx">j</span>
<span class="p">}</span>
<span class="p">}</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="s">&#34;bi-dimensional: &#34;</span><span class="p">,</span> <span class="nx">twoD</span><span class="p">)</span>
<span class="p">}</span>
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<p>Note que arrays aparecem na forma <code>[v1 v2 v3 ...]</code>
quando exibidos com <code>fmt.Println</code>.</p>
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<pre class="chroma">
<span class="gp">$</span> go run arrays.go
<span class="go">vazio: [0 0 0 0 0]
</span><span class="go">índice 4 alterado: [0 0 0 0 100]
</span><span class="go">valor índice 4: 100
</span><span class="go">len: 5
</span><span class="go">array inicializado:: [1 2 3 4 5]
</span><span class="go">bi-dimensional: [[0 1 2] [1 2 3]]</span></pre>
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<p class="next">
Próximo exemplo: <a href="slices">Slices</a>.
</p>
<p class="footer">
Por <a href="https://markmcgranaghan.com">Mark McGranaghan</a> e <a href="https://eli.thegreenplace.net">Eli Bendersky</a> | traduzido por <a href="https://github.com/lucassauro">Lucassauro</a> | <a href="https://github.com/lucassauro/gobyexample">contribua</a> | <a href="https://github.com/mmcgrana/gobyexample#license">licença</a>
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