title: Assign array key and add its value with the same key
body: <p>i have arrays like this,</p>
  
  <pre><code>array(
    [0]=&gt;111 //id
    [1]=&gt;5   //value to ad
    [2]=&gt;3   //value to ad
  )
  array(
    [0]=&gt;111
    [1]=&gt;3
    [2]=&gt;7   
  )
  array(
    [0]=&gt;111
    [1]=&gt;2
    [2]=&gt;1   
  )
  array(
    [0]=&gt;222
    [1]=&gt;5
    [2]=&gt;3   
  )
  </code></pre>
  
  <p>how can i filter those arrays that the result is to display it once per "id" and add the "value to add" if they have same "id". so the result will be:</p>
  
  <pre><code>array(
    [111]=&gt;array(
            [0]=&gt;10
            [1]=&gt;11
           )
    [222]=&gt;array(
            [0]=&gt;5
            [1]=&gt;3
           )
  )
  </code></pre>
  
  <p>Answers and suggestions are appreciated!</p>