PHP foreach loop show category name onces json multidimensional array

I have an multidimensional array in which there are three fields substitute name,substitute category and price. I have this is on foreach loop. I want to show category name once and under this substitute name.

     Array ( 
          [sub1] => 

     Array ( [substitute] => 2 
             [substitute_category] => 7 
             [substitute_price] => 123 ) 

         [sub2] => 

    Array ( 
           [substitute] => 3 
           [substitute_category] => 7 
           [substitute_price] => 139 
          )
         [sub3] =>

 Array ( [substitute] => 4 
         [substitute_category] => 7 
         [substitute_price] => 150 ) 
       ) 
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