title: Maximum Subarray Sum Array Created Repeated Concatenation
signature: function maximum_subarray_sum_array_created_repeated_concatenation(a, n, k)
test_code: using Printf
  
  # SOLUTION CODE
  # ============================================
  PLACEHOLDER_CODE_BODY
  
  # TESTING CODE 
  # ============================================
  function validate_solution(actual, expected)
      return actual == expected
  end
  
  function driver(a, n, k, expected)
      try
  
          if validate_solution(PLACEHOLDER_FN_NAME(a, n, k), expected)
              return "PASSED";
          end
          return "FAILED";
      catch exception_obj
          return string(Base.typename(typeof(exception_obj)).wrapper);
      end
  end
  
  function main()
      
      result = driver([5, 6, 12, 20, 23, 28, 33, 37, 47, 51, 53, 56, 63, 65, 65, 68, 69, 76, 76, 78, 83], 18, 20, 15540);
      @printf("TEST-0...%s\n",result);
      
      result = driver([68, 10, 52, -44, 34, -4, -34, 2, 50, -60, 50, 94, -98, -98, -44, -36, -4, -62, -2, -92, -70, -48, -78, -10, 94], 22, 22, 218);
      @printf("TEST-1...%s\n",result);
      
      result = driver([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], 34, 29, 522);
      @printf("TEST-2...%s\n",result);
      
      result = driver([71, 59, 21, 82, 73, 29, 30, 25, 21, 10, 85, 22, 60, 43, 49, 20, 34, 39, 69, 6, 44, 27, 50, 33, 57, 29, 65, 18, 68, 56, 50, 28], 23, 30, 29070);
      @printf("TEST-3...%s\n",result);
      
      result = driver([-84, -74, -74, -56, -54, -48, -48, -46, -42, -34, -32, -30, -18, -16, -16, 6, 12, 20, 24, 26, 30, 32, 34, 42, 42, 42, 44, 46, 46, 50, 50, 62, 72, 78, 90], 17, 23, 18);
      @printf("TEST-4...%s\n",result);
      
      result = driver([0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0], 16, 25, 300);
      @printf("TEST-5...%s\n",result);
      
      result = driver([3, 7, 11, 11, 26, 60, 68, 71, 77, 91, 95], 8, 10, 2570);
      @printf("TEST-6...%s\n",result);
      
      result = driver([28, 48, -86, -52, 6, 4, 30, 18, -32, 60, -2, 16, -88, -36], 8, 11, 134);
      @printf("TEST-7...%s\n",result);
      
      result = driver([1], 0, 0, -2147483648);
      @printf("TEST-8...%s\n",result);
      
      result = driver([76], 0, 0, -2147483648);
      @printf("TEST-9...%s\n",result);
      
  end
  
  main()
source_py: def maximum_subarray_sum_array_created_repeated_concatenation(a, n, k):
      max_so_far = (- 2147483648)
      max_ending_here = 0
      for i in range((n * k)):
          max_ending_here = (max_ending_here + a[(i % n)])
          if (max_so_far < max_ending_here):
              max_so_far = max_ending_here
          if (max_ending_here < 0):
              max_ending_here = 0
      return max_so_far
source_cpp: int maximum_subarray_sum_array_created_repeated_concatenation(vector<int> a, int n, int k) {
    int max_so_far = INT_MIN, max_ending_here = 0;
    for ( int i = 0;
    i < n * k;
    i ++ ) {
      max_ending_here = max_ending_here + a [ i % n ];
      if ( max_so_far < max_ending_here ) max_so_far = max_ending_here;
      if ( max_ending_here < 0 ) max_ending_here = 0;
    }
    return max_so_far;
  }