title: Chocolate Distribution Problem
signature: chocolateDistributionProblem(arr, n, m) {
test_code: import 'dart:convert';
  
  // SOLUTION CODE
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE 
  // ============================================
  bool validateSolution(int actual, int expected){
      return actual.toString() == expected.toString();
  }
  
  String driver(arr, n, m, int expected){
      try
      {
          if (validateSolution(PLACEHOLDER_FN_NAME(arr, n, m), expected)){
              return "PASSED";
          }
          return "FAILED";
      }catch(exception_object){
          return exception_object.runtimeType.toString();
      }
  }
  
  int main() {
  
      print("TEST-0...${driver(
          [2, 5, 11, 23, 33, 35, 39, 51, 52, 56, 74, 76, 76, 79, 85, 88, 93, 98], 16, 13, 
          65)
      }");
  
      print("TEST-1...${driver(
          [-94, -94, -88, -84, -74, -70, -56, -50, -48, -42, -34, -24, -18, -14, 0, 4, 4, 16, 16, 30, 36, 42, 52, 56, 72, 74, 76, 84, 88], 15, 28, 
          -1)
      }");
  
      print("TEST-2...${driver(
          [0, 0, 1, 1, 1, 1], 5, 5, 
          1)
      }");
  
      print("TEST-3...${driver(
          [3, 4, 5, 5, 12, 16, 16, 16, 18, 29, 37, 38, 40, 43, 44, 49, 57, 60, 62, 63, 67, 69, 73, 74, 75, 76, 78, 84, 85, 86, 88, 89, 92], 25, 18, 
          57)
      }");
  
      print("TEST-4...${driver(
          [-98, -80, -50, -44, -42, -36, -36, -28, -10, -8, -4, -2, 2, 10, 18, 18, 26, 32, 36, 56, 80, 86, 88, 90], 16, 12, 
          60)
      }");
  
      print("TEST-5...${driver(
          [0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1], 13, 14, 
          -1)
      }");
  
      print("TEST-6...${driver(
          [13, 15, 62, 65, 87], 3, 4, 
          -1)
      }");
  
      print("TEST-7...${driver(
          [-92, -88, -88, -80, -76, -62, -60, -60, -50, -48, -36, -36, -32, -26, -14, -8, 4, 18, 18, 22, 28, 30, 30, 32, 48, 48, 58, 60, 64, 72, 78, 82, 94], 31, 17, 
          90)
      }");
  
      print("TEST-8...${driver(
          [0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1], 9, 6, 
          1)
      }");
  
      print("TEST-9...${driver(
          [17, 23, 25, 38, 40, 53, 58, 73, 77], 8, 6, 
          35)
      }");
  
      return 0;
  }
source_py: def chocolate_distribution_problem(arr, n, m):
      if ((m == 0) or (n == 0)):
          return 0
      arr.sort()
      if (n < m):
          return (- 1)
      min_diff = sys.maxsize
      first = 0
      last = 0
      i = 0
      while (((i + m) - 1) < n):
          diff = (arr[((i + m) - 1)] - arr[i])
          if (diff < min_diff):
              min_diff = diff
              first = i
              last = ((i + m) - 1)
          i += 1
      return (arr[last] - arr[first])
source_cpp: int chocolate_distribution_problem(vector<int> arr, int n, int m) {
    if ( m == 0 || n == 0 ) return 0;
    sort(arr.begin(), arr.end());
    if ( n < m ) return - 1;
    int min_diff = INT_MAX;
    int first = 0, last = 0;
    for ( int i = 0;
    i + m - 1 < n;
    i ++ ) {
      int diff = arr [ i + m - 1 ] - arr [ i ];
      if ( diff < min_diff ) {
        min_diff = diff;
        first = i;
        last = i + m - 1;
      }
    }
    return ( arr [ last ] - arr [ first ] );
  }