title: Number Of Binary Trees For Given Preorder Sequence Length
signature: class Solution {
  
      public int NumberOfBinaryTreesForGivenPreorderSequenceLength(int n) {
test_code: using System;
  using System.Numerics;
  using System.Diagnostics;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  using System.Security.Cryptography;
  using System.Web.UI;
  using System.Web.Script.Serialization;
  
  // SOLUTION CODE
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE 
  // ============================================
  namespace EvaluatePrediction {
      class TestRunner {
          public bool ValidateSolution(int actual, int expected){
              return new JavaScriptSerializer().Serialize(actual) == new JavaScriptSerializer().Serialize(expected);
          }
  
          public string driver(int n, int expected){
              try{
                PLACEHOLDER_CLS_NAME solution_cls = new PLACEHOLDER_CLS_NAME();
                int pred_result = solution_cls.PLACEHOLDER_FN_NAME(n); 
                if (ValidateSolution(
                      pred_result,
                      expected)){
                  return "PASSED";
                }
                return "FAILED";
              } 
              catch (Exception exception_obj)
              {
                return exception_obj.GetType().FullName;
              }
          }
          static void Main(string[] args) {
              TestRunner runner = new TestRunner();
              String result;
              result = runner.driver(
                  15, 
                  9694845
              );
              Console.WriteLine(string.Format(
                  "TEST-0...{0}",
                  result)
              );result = runner.driver(
                  11, 
                  58786
              );
              Console.WriteLine(string.Format(
                  "TEST-1...{0}",
                  result)
              );result = runner.driver(
                  11, 
                  58786
              );
              Console.WriteLine(string.Format(
                  "TEST-2...{0}",
                  result)
              );result = runner.driver(
                  15, 
                  9694845
              );
              Console.WriteLine(string.Format(
                  "TEST-3...{0}",
                  result)
              );
          }
      }
  }
  
source_py: def number_of_binary_trees_for_given_preorder_sequence_length(n):
      BT = ([0] * (n + 1))
      BT[0] = BT[1] = 1
      for i in range(2, (n + 1)):
          for j in range(i):
              BT[i] += (BT[j] * BT[((i - j) - 1)])
      return BT[n]
source_cpp: int number_of_binary_trees_for_given_preorder_sequence_length(int n) {
    int BT [ n + 1 ];
    memset ( BT, 0, sizeof ( BT ) );
    BT [ 0 ] = BT [ 1 ] = 1;
    for ( int i = 2;
    i <= n;
    ++ i ) for ( int j = 0;
    j < i;
    j ++ ) BT [ i ] += BT [ j ] * BT [ i - j - 1 ];
    return BT [ n ];
  }