练习29: 如果（if）–笨方法学ruby在线-昊天SEO

这里是你接下要写的作业，这段介绍了if-statement （if 语句）。把这段输入进去，让它能够正确执行。然后我们看看你是否有收获。

<span class="nv">people</span> <span class="o">=</span> 20
<span class="nv">cats</span> <span class="o">=</span> 30
<span class="nv">dogs</span> <span class="o">=</span> 15

<span class="k">if</span> people < cats
  puts <span class="s2">"Too many cats! The world is doomed!"</span>
end

<span class="k">if</span> people > cats
  puts <span class="s2">"Not many cats! The world is saved!"</span>
end

<span class="k">if</span> people < dogs
  puts <span class="s2">"The world is drooled on!"</span>
end

<span class="k">if</span> people > dogs
  puts <span class="s2">"The world is dry!"</span>
end

dogs +<span class="o">=</span> 5

<span class="k">if</span> people ><span class="o">=</span> dogs
  puts <span class="s2">"People are greater than or equal to dogs."</span>
end

<span class="k">if</span> people <<span class="o">=</span> dogs
  puts <span class="s2">"People are less than or equal to dogs."</span>
end

<span class="k">if</span> <span class="nv">people</span> <span class="o">==</span> dogs
  puts <span class="s2">"People are dogs."</span>
end