title: Subarrays Distinct Elements
signature: pub fn subarrays_distinct_elements(arr: Vec<i32>, n: i32) -> i32 {
test_code: use std::collections::HashMap;
  use std::collections::HashSet;
  use std::cmp::*;
  use std::collections::*;
  use std::fmt::*; 
  
  
  // SOLUTION CODE
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE 
  // ============================================
  pub fn validate_solution(actual: i32, expected: i32)->bool{
  return actual==expected
  }
  pub fn driver(arr: Vec<i32>, n: i32, expected: i32)->String{
      if validate_solution(PLACEHOLDER_FN_NAME(arr, n), expected) {
        return "PASSED".to_string();
      };
      return "FAILED".to_string();
  
  }
  
  fn main() {
      println!("TEST-0...{}", driver(
        Vec::from([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
      ));
      
      println!("TEST-1...{}", driver(
        Vec::from([-8, 54, -22, 18, 20, 44, 0, 54, 90, -4, 4, 40, -74, -16]), 13, 
        335
      ));
      
      println!("TEST-2...{}", driver(
        Vec::from([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
      ));
      
      println!("TEST-3...{}", driver(
        Vec::from([36, 71, 36, 58, 38, 90, 17]), 4, 
        13
      ));
      
      println!("TEST-4...{}", driver(
        Vec::from([-90, -32, -16, 18, 38, 82]), 5, 
        35
      ));
      
      println!("TEST-5...{}", driver(
        Vec::from([1, 0, 1]), 2, 
        4
      ));
      
      println!("TEST-6...{}", driver(
        Vec::from([3, 11, 21, 25, 28, 28, 38, 42, 48, 53, 55, 55, 55, 58, 71, 75, 79, 80, 80, 94, 96, 99]), 20, 
        152
      ));
      
      println!("TEST-7...{}", driver(
        Vec::from([-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
      ));
      
      println!("TEST-8...{}", driver(
        Vec::from([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
      ));
      
      println!("TEST-9...{}", driver(
        Vec::from([19, 13, 61, 32, 92, 90, 12, 81, 52]), 5, 
        35
      ));
      
  }
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;
  }