title: Product Nodes K Th Level Tree Represented String
signature: function product_nodes_k_th_level_tree_represented_string(tree, k)
test_code: using Printf
  
  # SOLUTION CODE
  # ============================================
  PLACEHOLDER_CODE_BODY
  
  # TESTING CODE 
  # ============================================
  function validate_solution(actual, expected)
      return actual == expected
  end
  
  function driver(tree, k, expected)
      try
  
          if validate_solution(PLACEHOLDER_FN_NAME(tree, k), expected)
              return "PASSED";
          end
          return "FAILED";
      catch exception_obj
          return string(Base.typename(typeof(exception_obj)).wrapper);
      end
  end
  
  function main()
      
      result = driver("(0(5(6()())(4()(9()())))(7(1()())(3()())))", 2, 72);
      @printf("TEST-0...%s\n",result);
      
      result = driver("(8(3(2()())(6(5()())()))(5(10()())(7(13()())())))", 3, 15);
      @printf("TEST-1...%s\n",result);
      
      result = driver("(0(5(6()())(4()(9()())))(7(1()())(3()())))", 1, 35);
      @printf("TEST-2...%s\n",result);
      
      result = driver("(8(3(2()())(6(5()())()))(5(10()())(7(13()())())))", 2, 0);
      @printf("TEST-3...%s\n",result);
      
      result = driver("(8(3(2()())(6(5()())()))(5(10()())(7(13()())())))", 4, 1);
      @printf("TEST-4...%s\n",result);
      
      result = driver("(8(3(2()())(6(5()())()))(5(10()())(7(13()())())))", 100, 1);
      @printf("TEST-5...%s\n",result);
      
      result = driver("(0(5(6()())(4()(9()())))(7(1()())(3()())))", 3, 9);
      @printf("TEST-6...%s\n",result);
      
      result = driver("(0(5(6()())(4()(9()())))(7(1()())(3()())))", 0, 0);
      @printf("TEST-7...%s\n",result);
      
      result = driver("0010", 12, 1);
      @printf("TEST-8...%s\n",result);
      
      result = driver("kjtdgmy", 97, 1);
      @printf("TEST-9...%s\n",result);
      
  end
  
  main()
source_py: def product_nodes_k_th_level_tree_represented_string(tree, k):
      level = (- 1)
      product = 1
      n = len(tree)
      for i in range(0, n):
          if (tree[i] == '('):
              level += 1
          elif (tree[i] == ')'):
              level -= 1
          elif (level == k):
              product *= (int(tree[i]) - int('0'))
      return product
source_cpp: int product_nodes_k_th_level_tree_represented_string(string tree, int k) {
    int level = - 1;
    int product = 1;
    int n = tree . length ( );
    for ( int i = 0;
    i < n;
    i ++ ) {
      if ( tree [ i ] == '(' ) level ++;
      else if ( tree [ i ] == ')' ) level --;
      else {
        if ( level == k ) product *= ( tree [ i ] - '0' );
      }
    }
    return product;
  }