title: Subarrays Distinct Elements
signature: class Solution {
  
      public Integer subarraysDistinctElements(ArrayList<Integer> arr, Integer n) {
test_code: import static java.util.Map.entry;  
  import java.util.*;
  import java.lang.*;
  // TESTING CODE 
  // ============================================
  class QuestionEvaluator {
      public static String validateSolution(ArrayList<Integer> arr, Integer n, Integer expected){
          try{
              Driver driver = new Driver();
              if (driver.run(arr, n,expected)){
                  return "PASSED";
              }
              return "FAILED";
              
          } catch (Exception exception_obj){
              return exception_obj.getClass().getSimpleName();
          }
  
      }
      public static void main(String[] args) {
          String result;
          result = validateSolution(new ArrayList<>(Arrays.asList(3, 4, 5, 6, 12, 15, 16, 17, 20, 20, 22, 24, 24, 27, 28, 34, 37, 39, 39, 41, 43, 49, 49, 51, 55, 62, 63, 67, 71, 74, 74, 74, 77, 84, 84, 89, 89, 97, 99)), 24, 255);
          System.out.println(String.format("%s%s","TEST-0...",result));    
      
          result = validateSolution(new ArrayList<>(Arrays.asList(-8, 54, -22, 18, 20, 44, 0, 54, 90, -4, 4, 40, -74, -16)), 13, 335);
          System.out.println(String.format("%s%s","TEST-1...",result));    
      
          result = validateSolution(new ArrayList<>(Arrays.asList(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1)), 28, 30);
          System.out.println(String.format("%s%s","TEST-2...",result));    
      
          result = validateSolution(new ArrayList<>(Arrays.asList(36, 71, 36, 58, 38, 90, 17)), 4, 13);
          System.out.println(String.format("%s%s","TEST-3...",result));    
      
          result = validateSolution(new ArrayList<>(Arrays.asList(-90, -32, -16, 18, 38, 82)), 5, 35);
          System.out.println(String.format("%s%s","TEST-4...",result));    
      
          result = validateSolution(new ArrayList<>(Arrays.asList(1, 0, 1)), 2, 4);
          System.out.println(String.format("%s%s","TEST-5...",result));    
      
          result = validateSolution(new ArrayList<>(Arrays.asList(3, 11, 21, 25, 28, 28, 38, 42, 48, 53, 55, 55, 55, 58, 71, 75, 79, 80, 80, 94, 96, 99)), 20, 152);
          System.out.println(String.format("%s%s","TEST-6...",result));    
      
          result = validateSolution(new ArrayList<>(Arrays.asList(-16, -52, -4, -46, 54, 0, 8, -64, -82, -10, -62, -10, 58, 44, -28, 86, -24, 16, 44, 22, -28, -42, -52, 8, 76, -44, -34, 2, 88, -88, -14, -84, -36, -68, 76, 20, 20, -50)), 35, 1791);
          System.out.println(String.format("%s%s","TEST-7...",result));    
      
          result = validateSolution(new ArrayList<>(Arrays.asList(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1)), 27, 29);
          System.out.println(String.format("%s%s","TEST-8...",result));    
      
          result = validateSolution(new ArrayList<>(Arrays.asList(19, 13, 61, 32, 92, 90, 12, 81, 52)), 5, 35);
          System.out.println(String.format("%s%s","TEST-9...",result));    
      
      }
  }
  
  class Driver{
      public boolean run(ArrayList<Integer> arr, Integer n, Integer expected){
  
          PLACEHOLDER_CLS_NAME sol = new PLACEHOLDER_CLS_NAME();
          return validateSolution(sol.PLACEHOLDER_FN_NAME(arr, n),expected);
      }
      
      public boolean validateSolution(Integer actual, Integer expected){
          return actual.equals(expected);
      }
  }
  
  
  // SOLUTION CODE
  // ============================================
  PLACEHOLDER_CODE_BODY
source_py: def subarrays_distinct_elements(arr, n):
      s = []
      j = 0
      ans = 0
      for i in range(n):
          while ((j < n) and (arr[j] not in s)):
              s.append(arr[j])
              j += 1
          ans += (((j - i) * ((j - i) + 1)) // 2)
          s.remove(arr[i])
      return ans
source_cpp: int subarrays_distinct_elements(vector<int> arr, int n) {
    unordered_set < int > s;
    int j = 0, ans = 0;
    for ( int i = 0;
    i < n;
    i ++ ) {
      while ( j < n && s . find ( arr [ j ] ) == s . end ( ) ) {
        s . insert ( arr [ j ] );
        j ++;
      }
      ans += ( ( j - i ) * ( j - i + 1 ) ) / 2;
      s . erase ( arr [ i ] );
    }
    return ans;
  }