title: Check to see if all variable are equal to the same value in c++
body: <p>What is the easiest way to compare multiple variable to see if they are all the same value?
  For example if var1 = 53 and I want to check if var2 or var3 is equal to var1 and each other?
  So far I have done this:</p>
  
  <pre><code>if(row1==row2==row3==row4==col1==col2==col3==col4==diag1==diag2)
      cout &lt;&lt; "It is a magic square";
  else
      cout &lt;&lt; "Not a magic square";
  </code></pre>
  
  <p>However this doesn't seem to work.
  Thanks for you help.</p>