equal
  deleted
  inserted
  replaced
  
    
    
     3   | 
     3   | 
     4 def pow(A: Set[String], n: Int) : Set[String] = n match { | 
     4 def pow(A: Set[String], n: Int) : Set[String] = n match { | 
     5   case 0 => Set("") | 
     5   case 0 => Set("") | 
     6   case n => concat(A, pow(A, n- 1))  | 
     6   case n => concat(A, pow(A, n- 1))  | 
     7 }  | 
     7 }  | 
         | 
     8   | 
         | 
     9 val A = Set("a", "b", "c", "d", "e") | 
         | 
    10 val B = Set("a", "b", "c", "d", "") | 
         | 
    11 pow(A, 4).size  | 
         | 
    12 pow(B, 4).size  | 
         | 
    13   | 
     8   | 
    14   | 
     9 val A = Set("aa", "a") | 
    15 val A = Set("aa", "a") | 
    10 val B = Set("aaa", "aaaa") | 
    16 val B = Set("aaa", "aaaa") | 
    11 concat(A, B).size                     // -> 3   | 
    17 concat(A, B).size                     // -> 3   | 
    12   | 
    18   |