上一节你学到的逻辑组合的正式名称是「布尔逻辑表示式(boolean logic expression)」。在程序中,布尔逻辑可以说是无处不在。它们是电脑运算的基础和重要组成部分,掌握它们就跟学音乐掌握音阶一样重要。
在这节练习中,你将在 IRB 里使用到上节学到的逻辑表示式。先为下面的每一个逻辑问题写出你认为的答案,每一题的答案要嘛为 True 要嘛为 False。写完以后,你需要将 IRB 运行起来,把这些逻辑语句输入进去,确认你写的答案是否正确。
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<span class="nb">true </span>and <span class="nb">true</span> <span class="nb">false </span>and <span class="nb">true</span> <span class="nv">1</span> <span class="o">==</span> <span class="m">1</span> and <span class="nv">2</span> <span class="o">==</span> 1 <span class="s2">"test"</span> <span class="o">==</span> <span class="s2">"test"</span> <span class="nv">1</span> <span class="o">==</span> <span class="m">1</span> or <span class="m">2</span> !<span class="o">=</span> 1 <span class="nb">true </span>and <span class="nv">1</span> <span class="o">==</span> 1 <span class="nb">false </span>and <span class="m">0</span> !<span class="o">=</span> 0 <span class="nb">true </span>or <span class="nv">1</span> <span class="o">==</span> 1 <span class="s2">"test"</span> <span class="o">==</span> <span class="s2">"testing"</span> <span class="m">1</span> !<span class="o">=</span> <span class="m">0</span> and <span class="nv">2</span> <span class="o">==</span> 1 <span class="s2">"test"</span> !<span class="o">=</span> <span class="s2">"testing"</span> <span class="s2">"test"</span> <span class="o">==</span> 1 not <span class="o">(</span><span class="nb">true </span>and <span class="nb">false</span><span class="o">)</span> not <span class="o">(</span><span class="nv">1</span> <span class="o">==</span> <span class="m">1</span> and <span class="m">0</span> !<span class="o">=</span> 1<span class="o">)</span> not <span class="o">(</span><span class="nv">10</span> <span class="o">==</span> <span class="m">1</span> or <span class="nv">1000</span> <span class="o">==</span> 1000<span class="o">)</span> not <span class="o">(</span><span class="m">1</span> !<span class="o">=</span> <span class="m">10</span> or <span class="nv">3</span> <span class="o">==</span> 4<span class="o">)</span> not <span class="o">(</span><span class="s2">"testing"</span> <span class="o">==</span> <span class="s2">"testing"</span> and <span class="s2">"Zed"</span> <span class="o">==</span> <span class="s2">"Cool Guy"</span><span class="o">)</span> <span class="nv">1</span> <span class="o">==</span> <span class="m">1</span> and not <span class="o">(</span><span class="s2">"testing"</span> <span class="o">==</span> <span class="m">1</span> or <span class="nv">1</span> <span class="o">==</span> 0<span class="o">)</span> <span class="s2">"chunky"</span> <span class="o">==</span> <span class="s2">"bacon"</span> and not <span class="o">(</span><span class="nv">3</span> <span class="o">==</span> <span class="m">4</span> or <span class="nv">3</span> <span class="o">==</span> 3<span class="o">)</span> <span class="nv">3</span> <span class="o">==</span> <span class="m">3</span> and not <span class="o">(</span><span class="s2">"testing"</span> <span class="o">==</span> <span class="s2">"testing"</span> or <span class="s2">"Ruby"</span> <span class="o">==</span> <span class="s2">"Fun"</span><span class="o">)</span> |
