title: how to check multidimensional array for duplicated value
body: <p>i have this array and i don't want to remove duplicated values..
  i want to check if there are duplicates in the first value or not </p>
  
  <blockquote>
    <p>( [0] => 1500,[0] => 1111,  [0] => 1500)</p>
  </blockquote>
  
  <p>if there are then return true else return false how to do this ?</p>
  
  <pre><code>Array
  (
      [0] =&gt; Array
          (
              [0] =&gt; 1500
              [1] =&gt; first
              [2] =&gt; 
              [3] =&gt; 
              [4] =&gt; 50
              [5] =&gt; 
              [6] =&gt; 
          )
  
      [1] =&gt; Array
          (
              [0] =&gt; 1111
              [1] =&gt; second
              [2] =&gt; 
              [3] =&gt; 
              [4] =&gt; 10
              [5] =&gt; 
              [6] =&gt; 
          )
  
      [2] =&gt; Array
          (
              [0] =&gt; 1500
              [1] =&gt; third
              [2] =&gt; 
              [3] =&gt; 
              [4] =&gt; 100
              [5] =&gt; 
              [6] =&gt; 
          )
  
  
  
  )
  </code></pre>