answer_2.htm

软件设计师模拟试卷,点击里面的Exe文件可以随机出题

10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>，然后进入循环，循环体执行一次处理一个</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>ch</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>。进入循环，利用</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>kind</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>函数算出</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>ch</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>的类型</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>k</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>。（</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>2</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>）算法</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>2-1</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>大致流程如下：当</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>k</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>等于什么的时候把什么入栈；当</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>k</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>等于什么的时候且栈不为空的时候出栈，如果栈为空，打印错误消息，如果都不是，则读取文件的下一个字符再次进入循环。由上看出，入栈应是类型</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>k</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>为</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>1</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>，而出栈应该是类型</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>k</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>为</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>2</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>。在（</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>4</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>）下面出栈时，并没有用到栈的内容。在此就有些人认为栈中的内容没什么用了，随便压个</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>ch</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>，而且两个写的都是</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>ch</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>。其实从逻辑上就可以理解这种解答，如果压的是同样的数据，又是在同一位置出栈，算法大可置用一个</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>push</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>、</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>pop</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>就可以了。所以应该继续看后面的内容，以寻找正确的答案。当看到<span
lang=EN-US>&quot;</span></span><span lang=EN-US style='mso-bidi-font-size:10.5pt'>row&lt;-pop</span><span
style='mso-bidi-font-size:10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>（）</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>;col&lt;-pop</span><span
style='mso-bidi-font-size:10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>（）</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>;</span><span lang=EN-US
style='mso-bidi-font-size:10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>&quot;时，所有的疑惑就迎刃而解了，应把</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>row</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>和</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>col</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>压入栈。由于是先弹出</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>row</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>后弹出</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>col</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>，按栈的后进先出的规则，可知压入栈的是</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>col</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>，再压</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>row</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>。<span
lang=EN-US><o:p></o:p></span></span></p>

<p class=MsoNormal style='mso-layout-grid-align:none;text-autospace:none'><span
style='mso-bidi-font-size:10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>［问题</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>2</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>］<span
lang=EN-US><o:p></o:p></span></span></p>

<p class=MsoNormal style='mso-layout-grid-align:none;text-autospace:none'><span
style='mso-bidi-font-size:10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>【答案】判断条件</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>1</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>：</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>b</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>判断条件</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>2</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>：</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>e</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>判断条件</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>3</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>：</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>f<o:p></o:p></span></p>

<p class=MsoNormal align=left style='text-align:left;mso-layout-grid-align:
none;text-autospace:none'><span style='mso-bidi-font-size:10.5pt;font-family:
宋体;mso-hansi-font-family:"Times New Roman"'>【解析】因为后面有<span lang=EN-US>&quot;</span></span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>pop</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>（）</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>;row&lt;-pop</span><span
style='mso-bidi-font-size:10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>（）</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>;col&lt;-pop</span><span
style='mso-bidi-font-size:10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>（）</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>;</span><span lang=EN-US
style='mso-bidi-font-size:10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>&quot;</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>,</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>所以空（</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>5</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>）应填</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>col,</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>（</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>6</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>）应填</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>row</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>。又因为判断条件</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>1</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>为真时需要入栈，所以判断条件</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>1</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>应是判断字符是不是左括号，是就入栈，所以判断条件选</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>b</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>。判断条件</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>2</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>和</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>3</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>是相关联的，当</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>2</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>和</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>3</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>都为真时，要进行出栈操作，因此要判断栈是否为空。由此可以得到待判断条件</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>2</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>和</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>3</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>中，有一个必定是用来判断栈是否为空的。可以用栈顶元素来确定当前括号是否和栈中压入括号是同一类型的。前提是左括号类型已经入栈了，且在栈底，如果（</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>7</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>）压入的是</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>k</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>，即吻合。所以（</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>7</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>）应填</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>k</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>，这样判断括号是否匹配的条件就可以确定了，如果当前</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>ch</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>是右括号且当前栈顶的左括号类型与</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>ch</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>匹配，则匹配成功。应把<span
lang=EN-US>&quot;栈不空&quot;作为判断条件</span></span><span lang=EN-US
style='mso-bidi-font-size:10.5pt'>2</span><span style='mso-bidi-font-size:10.5pt;
font-family:宋体;mso-hansi-font-family:"Times New Roman"'>，<span lang=EN-US>&quot;栈顶元素表示的是与当前字符匹配的左括号&quot;作为判断条件</span></span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>3</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>。这样判断条件</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>2</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>填</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>e,</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>判断条件</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>3</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>填</span><span
lang=EN-US style='mso-bidi-font-size:10.5pt'>f</span><span style='mso-bidi-font-size:
10.5pt;font-family:宋体;mso-hansi-font-family:"Times New Roman"'>。</span><span
style='font-size:8.5pt;font-family:"MS Sans Serif";mso-font-kerning:0pt;
mso-ansi-language:ZH-CN'><o:p></o:p></span></p>

<p class=MsoNormal><span lang=EN-US><![if !supportEmptyParas]>&nbsp;<![endif]><o:p></o:p></span></p>

</div>

</body>

</html>