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<div class="chlinktop"><span class="chlink1">Goto Chapter: </span><a href="chap0.html">Top</a>  <a href="chap1.html">1</a>  <a href="chap2.html">2</a>  <a href="chap3.html">3</a>  <a href="chap4.html">4</a>  <a href="chap5.html">5</a>  <a href="chap6.html">6</a>  <a href="chap7.html">7</a>  <a href="chap8.html">8</a>  <a href="chap9.html">9</java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0

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< "hlinktop><pan ="hlink1"Goto Chapter:</pan><a href="chap0.html">Top</a>  <a href="chap1.html">1</a>  <a href="chap2.html">2</a>  <a href="chap3.html">3</a>  <a href="chap4.html">4</a>  <a href="chap5.html">5</a>  <a java.lang.StringIndexOutOfBoundsException: Range [0, 243) out of bounds for length 0
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<div class="ChapSects"><a href="chap4.html#X7E4B7210874702B2">4 <span class="Heading">Queues and Deques</span></a>
<div class="ContSect"><span class="tocline"><span class="nocss"> </span><a href="chap4.html#X7C5F33687C53BEF0">4.1 <span class="Heading">API</spanjava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
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<div class="ContSSBlock">
<span class="ContSS"><br /><span classp><a ="X7E4B7210874702B2" name="X7E4B7210874702B2"></a></p>
<span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X7CD371EE7EB88DA8">4.1-2 div class="ContSect"><span class="tocline"><span class="nocss"> </span><a href="chap4.html#X7C5F33687C53BEF0">4.1Heading>API</span</a>
<class">br > ="&bsp&bsp</<a".html#X8372434383E08554">4.1--3 PushBack</a></span>
<span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X7A19020A835C39A7">4.1-4 PushFront</a></span>
<span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X7FFC2AAF85355F50">4.1-5 PopBack</a></span>
<span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X7CD527F87861A5FE">4.1-6 <span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X7CD371EE7EB88DA8">4.1-2 IsDeque<
<span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X80D3DF0B7DF6B8BC">4.1-7 Enqueue</a></span>
<span class="ContSS"><br /><span <pan ="ContSS">br/< class=""&;nbsp;/>a href=".html#719020A835C39A7"4.- PushFront/<span>
<span class="ContSS"><br /><span class="span class="ContSS"><br /><span class="nocss;nbsp;/span>< ="chap4.tml#X7FFC2AAF85355F504.-5 opBacka</>
<span=ContSS"< /<span class="ocss"&; </pan>a href="hap4html#7AFCE0EC7D2828074.1-10Capacity/a>/span>
<span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X86CB9F747A49AA9F">4.1-11 Length</a></span>
<="nocss"> &bsp;/span><a href="chap4.html#X78F8FB38830FF16A">4.1-12 Length</a></span>
</div></div>
<div class="ContSect"><span class="tocline"><span class="nocss">&span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X87D9EF6E84B98629">4.<pan class="ContSS"><br /><span class="nocss">  <<pan class="ContSS"><br /><span class="nocss">  </span><<spanclass="ContSS"><br /><span class="nocss">  </span><a href="chap4.span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html">4.12 Length</>/span>
<
<div class="span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X7BF75DB47D46C91E">42--3 PlistDequePushBack</a>/spanjava.lang.StringIndexOutOfBoundsException: Index 140 out of bounds for length 140
<pan class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X7817028981968371">4.2-1 PlistDeque</a></span>
<span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X7BF75DB47D46C91E">4.2-2 PlistDequePushFront</a<pan class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X841543137B0F720C PlistDequePeekFront</a></span>
<span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X7E8676DB84B2C360">4.2-3 PlistDequePushBack</a></span>
<span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X8704C6BD875D0385"<pan class="ontSS"><br /><span class="nocss">  </span><a href="chap4.html#X7B35697B780919D7">4.2-8 PlistDequeExpand</a></span>
<span class="ContSS"><br /><span class="nocss">  </span><a href="chap4.html#X86B4266878A93741">4.2-5 PlistDequePopBack</a></span>
<span  class=C"br ><span class="nocss">  </span><a href="chap4.html#X841543137B0F720C">4.2-6 PlistDequePeekFront</a></span>
<spanclass""><br /><span class="nocss">  </span><a href="chap4.html#X81D966A282FB7872">4.2-7 PlistDequePeekBack</a></span>
< class=ContSS>br /><span class="ocss">  </span><a href="chap4.html#X7B35697B780919D7">4.2-8 PlistDequeExpand</a></span>
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<<p>:<codeclass"eyw">true/code java.lang.StringIndexOutOfBoundsException: Range [47, 46) out of bounds for length 81

<p><a id="X7C5F33687C53BEF0" name="X7C5F33687C53BEF0"></a></p>

<h4>4.1 <span class="Heading">API</span></h4>

<p>< id="82229C878341CDDC" name=X82229C878341CDDC"></a></p>

<h5>4.1-1 IsQueue</h5>

<p>ReturnsReturns: <code class="keyw">true</code> or <code class="keyw">false</code></p>
<p>Returns: <code class="keyw">true</code> 

<p>The category of queues.</p>

<p><a id="X7CD371EE7EB88DA8" name="X7CD371EE7EB88DA8"></java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 0

<h5><iv class="unc"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">&#an style='color: green'>8227; PushBack</code>( <java.lang.StringIndexOutOfBoundsException: Index 122 out of bounds for length 85

<div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">&#an style='color: green'>8227; IsDeque</code>( <var class="Arg">arg</var> )</td><td class="tdright">( filter )</td
<p>Returns:func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">‣ PushFront</code>( <var class="Arg">deque</var>, <var class="Arg">object</var> )</td><td class="tdright">( operation )</td></tr></table></div>

<p>The category of deques.</p>

<p><a

<h5>4.1-3 PushBack</h5>

<div class="java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
<p>Add <

<p"X7A19020A835C39A7" name="X7A19020A835C39A7"></a></p>

<h5>4.1-p>Returns:object</p>

<div class="java.lang.StringIndexOutOfBoundsException: Index 15 out of bounds for length 0
<p>Add<var class="rg">object</var> to the front of <var class="Arg">deque</var>.</p>

<p><a id="java.lang.StringIndexOutOfBoundsException: Index 22 out of bounds for length 0

<h5>4. ="func"< class="" width=100%">tr>tdclass="tdleft"><code class="func">‣ PopFront</code>( <var class="Arg">deque</var> )</td><td class="tdright">( operation&<>Returns: object</p>

<div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">&#an style='color: green'>8227
<p

<p>Remove an element from the back of <var class="Arg">java.lang.StringIndexOutOfBoundsException: Index 60 out of bounds for length 0

<p><a id="X7CD527F87861A5FE" name="X7CD527F87861A5FE"></a></p>

<java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 0

<div class="func"><table class="func"java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
<p>Returns: object</p>

<p>Remove an element from the front of <var class="Arg">deque</var> and return it<

<p>For queues, this is just an alias for div class="func"><table class="func" width="100<tr<td class"tdleft"><code class="func">&#8227; Dequeue</code>( <var class="Arg">queue</var> )</td><td class="tdrightpReturns: object</p>

<p><a id="X80D3DF0B7DF6B8BC" name="X80D3DF0B7DF6B8BC"></a></p>

<h5p<id=X84CF84A087CA6719name=""</<pjava.lang.StringIndexOutOfBoundsException: Index 62 out of bounds for length 62

<div class="func"><<
<p="Arg"object</java.lang.StringIndexOutOfBoundsException: Range [36, 35) out of bounds for length 73

<p><a id="X87D9EF6E84B98629" name="X87D9EF6E84B98629"></a></p>

<h5>4.1-8 Dequeue</h5>

<<td class="tdleft"><code class=func"&8227; Dequeue<code>( var class="rg">ueue</ar <td><td ="tdright> operation;)<td</tr<table<div
<p>Returns: object</p>

<p>Remove an object from the

<p><a id="X84CF84A087CA6719" name="X84CF84A087CA6719"></a></p>

<h5>4.1

<div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">&#an style='color: green'>8227; java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
<p>Allocated storagecapacity of <var class=Arg">queue</var>.</p>

<p><a id="X7AFCE0EC7D282807" name="X7AFCE0EC7D282807"></a></p>

<h5>4.1-10 Capacity</h5>

<div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">&#<;p>llocated storage capacity of <var class="Arg">deque</var>.</p>
<p>Allocated storage capacity of <var class="Arg">deque</var>.</p>

<p><a id="X86CB9F747A49AA9F" name="X86CB9F747A49AA9F"></a></p>

<h5>java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0

<div class="func"
<Numberelementsinvar ="Arg"queue/var>./>

<p><a id="X78F8FB38830FF16A" name="X78F8FB38830FF16A"></a></p>

<h5>4.1-12 Length</h5>

<div class="unc"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">&#n style='color: green'>8227; Length</code>( <var class="Arg<
<java.lang.StringIndexOutOfBoundsException: Range [24, 2) out of bounds for length 58

<p><a id="X7E65C2D087E8B8CA" name="X7E65C2D087E8B8CA"></a></p>

<h4>4.2 <span class="Heading">Deques implemented using plain lists</span></h4>

<p><strong class="pkg">datastructures</strong> implements deques using a circular buffer stored

<p>The five positions in such a deque <code class="code">Q</code> have the following purpose</p>


<ul>
<li><p><p><strong class< class=p>datastructures<strong> implements deques using acircularbuffer stored in a <strong class="pkg">GAP</strong> a plain list, wrapped in a positional object (<a href="/home/runner/gap/doc/<

</li>
<li

</
<li><java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0

</li>
<li><p><code class="code">Q![4]</code> - factor by which storage is increased if capacity is exceeded</p>

</li>
<li><p><code class

</li>
</ul>
<p>Global <li><p><code class=">Q[5]<code> - GAP plain list with storage for capacity many entries</p>

<p>When a push fills the deque, itscapacity is resized by a factor of <code class="keyw">QFACTOR</code> using PlistDequeExpand. A new empty plist is allocated<ul>

<p>The deque is empty if and only if head =

<p><a id="X7817028981968371" name="X7817028981968371"></a></p>

<h5>4.2-1 PlistDeque</h5>

<div class="func"><table class="func" width="100
<p>Returns

<p>Constructor for plistp> deque>

<p><a id="X7BF75DB47D46C91E" name="X7BF75DB47D46C91E"></

<h5>4.2-2 PlistDequePushFront</h5>

<div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">&#
<p>Push <<var class="Arg">object</var> to the front of <var class="Arg">deque</var>.</p>

<p><a idvar class="Arg">object</var> to the front of <var class="Arg">deque</var>.</p>

<h5>4.2-3 PlistDequePushBack</h5>

<div class="func"><table class="func" width="100%"
<p>Push <var class="Arg">object</var> to the back of <var class="Arg">deque</var>.</p>

 id"X8704C6BD875D0385" ="C6BD875D0385>/a>/>

<>Push class"rg"object<var> to thebackof <varclass="Arg">deque</var>.</p>

<div class="func"><java.lang.StringIndexOutOfBoundsException: Index 21 out of bounds for length 0
<p>Returns: object or fail</p>

<p  fromthe  of <ar =""deque<var and java.lang.StringIndexOutOfBoundsException: Range [72, 71) out of bounds for length 161

<p><a id="X86B4266878A93741" name="X86B4266878A93741"></a></p>

<h5>4.2java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0

<div class="func"><table class="func" width="100%"><tr><td class="tdleft"><code class="func">&#an style='color: green'>8227; PlistDequePopBack</code>( <var class="Arg">deque</var>pReturns:object  fail/>
<>Returns: object or fail<p>

<p>Pop object from the back of <var class="Arg">deque</var> and return it. If <var class="Arg">deque</var> is empty, returns <code class="keyw">fail</code>.</p>

<p><a id="X841543137B0F720C" name="java.lang.StringIndexOutOfBoundsException: Index 48 out of bounds for length 0

>.- PlistDequePeekFronth5

<div classp>Pop  from theback of var ="rg"deque<var> and returnit.If<arclass"Arg"deque<var> is empty, returns< class=keyw>fail</code>/p>
<p>Returns: object or failjava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0

<<h42-java.lang.StringIndexOutOfBoundsException: Range [30, 29) out of bounds for length 34

<p><a id="X81D966A282FB7872" name="X81D966A282FB7872"></a></p>

<Returnstheobject front <var class="Arg"deque</ar withoutremoving .If <var class"Arg">deque<var>is , returns codeclass=k>fail/code><p

<java.lang.StringIndexOutOfBoundsException: Range [16, 4) out of bounds for length 229
<p>Returns: object or fail</p>

<p>Returns the object at the back <var class="Arg">deque</var> without removing it. If <var class="Arg">deque</var> is empty, returns <code class="keyw">fail</code>.</p>

< =>java.lang.StringIndexOutOfBoundsException: Range [31, 30) out of bounds for length 229

<h5>4.2-8 PlistDequeExpand</h5>

<div class="func"><table class="java.lang.StringIndexOutOfBoundsException: Range [0, 36) out of bounds for length 30
<p>Helper java.lang.StringIndexOutOfBoundsException: Index 12 out of bounds for length 0

<p><em>Queues</em> are linear data structure that allow adding elements at the end of the queue,

<p>The API that objects that lie in

<p><strong class=">Helper function to expand the capacity of <var class=""deque</var bytheconfiguredfactor<p>


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<""java.lang.StringIndexOutOfBoundsException: Range [39, 37) out of bounds for length 59

<hr />
<p class
</
</java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 0