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<p style='layout-grid-mode:char'><b><span lang=EN-US style='letter-spacing:
1.0pt'>6．算法示例</span></b><span lang=EN-US><o:p></o:p></span></p>
<p style='layout-grid-mode:char'><span style='letter-spacing:1.0pt'> （<span
lang=EN-US>1）</span></span><span lang=EN-US style='font-size:7.0pt;font-family:
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<p style='layout-grid-mode:char'><span lang=EN-US><br clear=all>
<span style='letter-spacing:1.0pt'>欧几里德算法——求两个自然数的最大公约数</span> <o:p></o:p></span></p>
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<p style='layout-grid-mode:char'><span style='letter-spacing:1.0pt'> （<span
lang=EN-US>2）顺序查找算法—— 在N个字符串集合中，查找有无特定的字符串存在 </span></span><span lang=EN-US><o:p></o:p></span></p>
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<p style='layout-grid-mode:char'><span lang=EN-US> <o:p></o:p></span></p>
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clear=all>
<span style='letter-spacing:1.0pt'> </span><o:p></o:p></span></p>
<p class=MsoNormal align=center style='text-align:center;layout-grid-mode:char'><b><span
lang=EN-US style='font-size:14.0pt;color:#000099;letter-spacing:1.0pt'>4.2</span></b><b><span
lang=EN-US style='font-size:7.0pt;font-family:"Times New Roman";color:#000099;
letter-spacing:1.0pt'> </span></b><b><span style='font-size:14.0pt;
color:#000099;letter-spacing:1.0pt'>顺序结构</span></b> <span lang=EN-US><o:p></o:p></span></p>
<p style='layout-grid-mode:char'><b><span style='letter-spacing:1.0pt'> <span
lang=EN-US>1.</span></span></b><b><span lang=EN-US style='font-size:7.0pt;
font-family:"Times New Roman";letter-spacing:1.0pt'> </span><span
style='letter-spacing:1.0pt'>赋值语句</span></b><span lang=EN-US><o:p></o:p></span></p>
<p style='layout-grid-mode:char'><span lang=EN-US style='letter-spacing:1.0pt'> 赋值语句是任何程序设计中最基本的语句，赋值语句都时顺序执行的。赋值语句的形式为：</span><span
lang=EN-US><o:p></o:p></span></p>
<p style='layout-grid-mode:char'><span lang=EN-US style='letter-spacing:1.0pt'>
<b><span style='color:blue'> 变量名 = 表达式</span></b></span><span lang=EN-US><o:p></o:p></span></p>
<p style='layout-grid-mode:char'><span lang=EN-US style='letter-spacing:1.0pt'> </span> <span
style='letter-spacing:1.0pt'>它的作用是计算右边表达式的值，然后赋给左边的变量，表达式的类型应该与变量名的类型一致。</span><span
lang=EN-US><o:p></o:p></span></p>
<p style='layout-grid-mode:char'><b> <span lang=EN-US style='letter-spacing:
1.0pt'>2. 使用说明</span></b><span lang=EN-US><o:p></o:p></span></p>
<p style='layout-grid-mode:char'><span style='letter-spacing:1.0pt'> （<span
lang=EN-US>1）当表达式为数值型而与变量精度不同时，强制转换成左边变量的精度；</span></span><span lang=EN-US><br>
<span style='letter-spacing:1.0pt'>（2）当表达式是数字字符串，左边变量是数值类型，自动转换成数值类型再赋值，但当表达式中有非数字字符或空串，则出错。</span><br>
<span style='letter-spacing:1.0pt'>（3）任何非字符类型赋值给字符类型，自动转换为字符类型；</span><br>
<span style='letter-spacing:1.0pt'>（4）当逻辑型赋值给数值型时，True转换为 -1，False转换为0；反之，非0转换为True，0转换为False；</span><br>
<span style='letter-spacing:1.0pt'>（5）赋值号左边的变量只能是变量，不能是常量、常数符号、表达式，否则报错；</span><br>
<span style='letter-spacing:1.0pt'>（6）不能在一句赋值语句中，同时给各变量赋值；</span><br>
<span style='letter-spacing:1.0pt'>（7）在条件表达式中出现的<b><span style='color:blue'>
= </span></b>是等号，系统会根据<b><span style='color:blue'> = </span></b>号的位置，自动判断是否为赋值号；</span><br>
<span style='letter-spacing:1.0pt'>（8）注意N=N+1 是累加中常见的赋值语句，表示将N变量中的值加1后再赋值给N。</span><o:p></o:p></span></p>
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style='font-size:10.0pt;color:#333399'>N <o:p></o:p></span></p>
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<p class=MsoNormal align=center style='text-align:center'><span
style='font-size:10.0pt;color:#333399'>执行了<span lang=EN-US>N=N+1后<o:p></o:p></span></span></p>
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<p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
style='font-size:10.0pt;color:#333399'>N<o:p></o:p></span></p>
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<p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
style='font-size:10.0pt;color:#333399'>5<o:p></o:p></span></p>
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<p class=MsoNormal align=center style='text-align:center'><span lang=EN-US
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<p align=center style='text-align:center;layout-grid-mode:char'><b><span
lang=EN-US style='font-size:14.0pt;letter-spacing:1.0pt'>4.3</span></b><b><span
lang=EN-US style='font-size:7.0pt;font-family:"Times New Roman";letter-spacing:
1.0pt'> </span></b><b><span lang=EN-US style='font-size:14.0pt;
letter-spacing:1.0pt'> 选择结构（或称分支结构)</span></b><span lang=EN-US> <o:p></o:p></span></p>
<p style='layout-grid-mode:char'><b><span lang=EN-US style='font-size:14.0pt'>1.1.
IF条件语句<br>
<br>
</span></b><strong><span style='mso-ascii-font-family:"Times New Roman";
mso-hansi-font-family:"Times New Roman"'>（</span></strong><strong><span
lang=EN-US style='font-family:"Times New Roman"'>1</span></strong><strong><span
style='mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"'>）</span></strong><strong><span
lang=EN-US style='font-family:"Times New Roman"'>If</span></strong><strong><span
style='mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"'>……</span></strong><strong><span
lang=EN-US style='font-family:"Times New Roman"'>Then</span></strong><strong><span
style='mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"'>语句（单分支结构</span></strong><strong><span
style='font-family:"Times New Roman"'> <span lang=EN-US>F</span></span></strong><strong><span
style='mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"'>）</span></strong><b><span
lang=EN-US style='font-size:14.0pt'><br>
</span><strong><span Roman? New Times> 语句形式：</span></strong></b><b><span
lang=EN-US style='font-size:14.0pt'><br>
</span> <span lang=EN-US>1）<span style='color:#0033FF'>If</span></span></b><b><span
lang=EN-US style='font-size:14.0pt'> </span><span lang=EN-US><<span
style='color:#990000'>表达式</span>> <span style='color:blue'>Then </span></span></b><b><span
lang=EN-US style='font-size:14.0pt'><br>
</span><span style='color:red'> 语句块</span><span lang=EN-US><br>
<span style='color:blue'> End If</span></span></b><span lang=EN-US> <o:p></o:p></span></p>
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