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  - test_1008_construct_binary_search_tree_from_preorder_traversal.rb
  - test_1019_next_greater_node_in_linked_list.rb
  - test_1023_camelcase_matching.rb
  - test_1026_maximum_difference_between_node_and_ancestor.rb
  - test_102_binary_tree_level_order_traversal.rb
  - test_1038_binary_search_tree_to_greater_sum_tree.rb
  - test_103_binary_tree_zigzag_level_order_traversal.rb
  - test_1043_partition_array_for_maximum_sum.rb
  - test_105_construct_binary_tree_from_preorder_and_inorder_traversal.rb
  - test_106_construct_binary_tree_from_inorder_and_postorder_traversal.rb
  - test_1079_letter_tile_possibilities.rb
  - test_107_binary_tree_level_order_traversal_ii.rb
  - test_1081_smallest_subsequence_of_distinct_characters.rb
  - test_109_convert_sorted_list_to_binary_search_tree.rb
  - test_1110_delete_nodes_and_return_forest.rb
  - test_1111_maximum_nesting_depth_of_two_valid_parentheses_strings.rb
  - test_1123_lowest_common_ancestor_of_deepest_leaves.rb
  - test_113_path_sum_ii.rb
  - test_114_flatten_binary_tree_to_linked_list.rb
  - test_1161_maximum_level_sum_of_a_binary_tree.rb
  - test_116_populating_next_right_pointers_in_each_node.rb
  - test_1171_remove_zero_sum_consecutive_nodes_from_linked_list.rb
  - test_117_populating_next_right_pointers_in_each_node_ii.rb
  - test_11_container_with_most_water.rb
  - test_1209_remove_all_adjacent_duplicates_in_string_ii.rb
  - test_120_triangle.rb
  - test_1247_minimum_swaps_to_make_strings_equal.rb
  - test_1248_count_number_of_nice_subarrays.rb
  - test_1249_minimum_remove_to_make_valid_parentheses.rb
  - test_1261_find_elements_in_a_contaminated_binary_tree.rb
  - test_1288_remove_covered_intervals.rb
  - test_128_longest_consecutive_sequence.rb
  - test_129_sum_root_to_leaf_numbers.rb
  - test_12_integer_to_roman.rb
  - test_1302_deepest_leaves_sum.rb
  - test_1305_all_elements_in_two_binary_search_trees.rb
  - test_1310_xor_queries_of_a_subarray.rb
  - test_1315_sum_of_nodes_with_even_valued_grandparent.rb
  - test_1325_delete_leaves_with_a_given_value.rb
  - test_1329_sort_the_matrix_diagonally.rb
  - test_1338_reduce_array_size_to_the_half.rb
  - test_1339_maximum_product_of_splitted_binary_tree.rb
  - test_133_clone_graph.rb
  - test_1343_number_of_sub_arrays_of_size_k_and_average_greater_than_or_equal_to_threshold.rb
  - test_1347_minimum_number_of_steps_to_make_two_strings_anagram.rb
  - test_134_gas_station.rb
  - test_1358_number_of_substrings_containing_all_three_characters.rb
  - test_1367_linked_list_in_binary_tree.rb
  - test_1376_time_needed_to_inform_all_employees.rb
  - test_1381_design_a_stack_with_increment_operation.rb
  - test_1382_balance_a_binary_search_tree.rb
  - test_1387_sort_integers_by_the_power_value.rb
  - test_138_copy_list_with_random_pointer.rb
  - test_1395_count_number_of_teams.rb
  - test_1396_design_underground_system.rb
  - test_1400_construct_k_palindrome_strings.rb
  - test_142_linked_list_cycle_ii.rb
  - test_1433_check_if_a_string_can_break_another_string.rb
  - test_143_reorder_list.rb
  - test_1442_count_triplets_that_can_form_two_arrays_of_equal_xor.rb
  - test_1448_count_good_nodes_in_binary_tree.rb
  - test_1457_pseudo_palindromic_paths_in_a_binary_tree.rb
  - test_1461_check_if_a_string_contains_all_binary_codes_of_size_k.rb
  - test_146_lru_cache.rb
  - test_1472_design_browser_history.rb
  - test_147_insertion_sort_list.rb
  - test_1481_least_number_of_unique_integers_after_k_removals.rb
  - test_148_sort_list.rb
  - test_1492_the_kth_factor_of_n.rb
  - test_1504_count_submatrices_with_all_ones.rb
  - test_150_evaluate_reverse_polish_notation.rb
  - test_151_reverse_words_in_a_string.rb
  - test_1525_number_of_good_ways_to_split_a_string.rb
  - test_1529_minimum_suffix_flips.rb
  - test_1530_number_of_good_leaf_nodes_pairs.rb
  - test_1557_minimum_number_of_vertices_to_reach_all_nodes.rb
  - test_155_min_stack.rb
  - test_15_3sum.rb
  - test_1609_even_odd_tree.rb
  - test_1630_arithmetic_subarrays.rb
  - test_1641_count_sorted_vowel_strings.rb
  - test_165_compare_version_numbers.rb
  - test_1669_merge_in_between_linked_lists.rb
  - test_1670_design_front_middle_back_queue.rb
  - test_1679_max_number_of_k_sum_pairs.rb
  - test_167_two_sum_ii_input_array_is_sorted.rb
  - test_1685_sum_of_absolute_differences_in_a_sorted_array.rb
  - test_16_3sum_closest.rb
  - test_1706_where_will_the_ball_fall.rb
  - test_1721_swapping_nodes_in_a_linked_list.rb
  - test_173_binary_search_tree_iterator.rb
  - test_1780_check_if_number_is_a_sum_of_powers_of_three.rb
  - test_1797_design_authentication_manager.rb
  - test_179_largest_number.rb
  - test_17_letter_combinations_of_a_phone_number.rb
  - test_1814_count_nice_pairs_in_an_array.rb
  - test_1823_find_the_winner_of_the_circular_game.rb
  - test_1829_maximum_xor_for_each_query.rb
  - test_1834_single_threaded_cpu.rb
  - test_1845_seat_reservation_manager.rb
  - test_1877_minimize_maximum_pair_sum_in_array.rb
  - test_187_repeated_dna_sequences.rb
  - test_189_rotate_array.rb
  - test_1910_remove_all_occurrences_of_a_substring.rb
  - test_1985_find_the_kth_largest_integer_in_the_array.rb
  - test_1996_the_number_of_weak_characters_in_the_game.rb
  - test_199_binary_tree_right_side_view.rb
  - test_19_remove_nth_node_from_end_of_list.rb
  - test_2007_find_original_array_from_doubled_array.rb
  - test_200_number_of_islands.rb
  - test_2023_number_of_pairs_of_strings_with_concatenation_equal_to_target.rb
  - test_204_count_primes.rb
  - test_2058_find_the_minimum_and_maximum_number_of_nodes_between_critical_points.rb
  - test_2063_vowels_of_all_substrings.rb
  - test_2074_reverse_nodes_in_even_length_groups.rb
  - test_208_implement_trie_prefix_tree.rb
  - test_2091_removing_minimum_and_maximum_from_array.rb
  - test_2095_delete_the_middle_node_of_a_linked_list.rb
  - test_2096_step_by_step_directions_from_a_binary_tree_node_to_another.rb
  - test_209_minimum_size_subarray_sum.rb
  - test_2109_adding_spaces_to_a_string.rb
  - test_2116_check_if_a_parentheses_string_can_be_valid.rb
  - test_2121_intervals_between_identical_elements.rb
  - test_2125_number_of_laser_beams_in_a_bank.rb
  - test_2130_maximum_twin_sum_of_a_linked_list.rb
  - test_2131_longest_palindrome_by_concatenating_two_letter_words.rb
  - test_2149_rearrange_array_elements_by_sign.rb
  - test_2150_find_all_lonely_numbers_in_the_array.rb
  - test_215_kth_largest_element_in_an_array.rb
  - test_2161_partition_array_according_to_given_pivot.rb
  - test_2165_smallest_value_of_the_rearranged_number.rb
  - test_2177_find_three_consecutive_integers_that_sum_to_a_given_number.rb
  - test_2181_merge_nodes_in_between_zeros.rb
  - test_2196_create_binary_tree_from_descriptions.rb
  - test_2221_find_triangular_sum_of_an_array.rb
  - test_2225_find_players_with_zero_or_one_losses.rb
  - test_2233_maximum_product_after_k_increments.rb
  - test_2265_count_nodes_equal_to_average_of_subtree.rb
  - test_2266_count_number_of_texts.rb
  - test_227_basic_calculator_ii.rb
  - test_2295_replace_elements_in_an_array.rb
  - test_22_generate_parentheses.rb
  - test_230_kth_smallest_element_in_a_bst.rb
  - test_2326_spiral_matrix_iv.rb
  - test_235_lowest_common_ancestor_of_a_binary_search_tree.rb
  - test_236_lowest_common_ancestor_of_a_binary_tree.rb
  - test_2375_construct_smallest_number_from_di_string.rb
  - test_237_delete_node_in_a_linked_list.rb
  - test_238_product_of_array_except_self.rb
  - test_2390_removing_stars_from_a_string.rb
  - test_240_search_a_2d_matrix_ii.rb
  - test_2415_reverse_odd_levels_of_binary_tree.rb
  - test_2425_bitwise_xor_of_all_pairings.rb
  - test_2429_minimize_xor.rb
  - test_24_swap_nodes_in_pairs.rb
  - test_2657_find_the_prefix_common_array_of_two_arrays.rb
  - test_2683_neighboring_bitwise_xor.rb
  - test_284_peeking_iterator.rb
  - test_287_find_the_duplicate_number.rb
  - test_299_bulls_and_cows.rb
  - test_29_divide_two_integers.rb
  - test_2_add_two_numbers.rb
  - test_300_longest_increasing_subsequence.rb
  - test_304_range_sum_query_2d_immutable.rb
  - test_316_remove_duplicate_letters.rb
  - test_318_maximum_product_of_word_lengths.rb
  - test_3223_minimum_length_of_string_after_operations.rb
  - test_328_odd_even_linked_list.rb
  - test_331_verify_preorder_serialization_of_a_binary_tree.rb
  - test_334_increasing_triplet_subsequence.rb
  - test_33_search_in_rotated_sorted_array.rb
  - test_341_flatten_nested_list_iterator.rb
  - test_347_top_k_frequent_elements.rb
  - test_34_find_first_and_last_position_of_element_in_sorted_array.rb
  - test_36_valid_sudoku.rb
  - test_371_sum_of_two_integers.rb
  - test_377_combination_sum_iv.rb
  - test_378_kth_smallest_element_in_a_sorted_matrix.rb
  - test_380_insert_delete_getrandom_o1.rb
  - test_382_linked_list_random_node.rb
  - test_388_longest_absolute_file_path.rb
  - test_38_count_and_say.rb
  - test_394_decode_string.rb
  - test_398_random_pick_index.rb
  - test_39_combination_sum.rb
  - test_3_longest_substring_without_repeating_characters.rb
  - test_400_nth_digit.rb
  - test_402_remove_k_digits.rb
  - test_417_pacific_atlantic_water_flow.rb
  - test_424_longest_repeating_character_replacement.rb
  - test_429_n_ary_tree_level_order_traversal.rb
  - test_435_non_overlapping_intervals.rb
  - test_437_path_sum_iii.rb
  - test_438_find_all_anagrams_in_a_string.rb
  - test_43_multiply_strings.rb
  - test_442_find_all_duplicates_in_an_array.rb
  - test_443_string_compression.rb
  - test_445_add_two_numbers_ii.rb
  - test_449_serialize_and_deserialize_bst.rb
  - test_450_delete_node_in_a_bst.rb
  - test_451_sort_characters_by_frequency.rb
  - test_453_minimum_moves_to_equal_array_elements.rb
  - test_456_132_pattern.rb
  - test_462_minimum_moves_to_equal_array_elements_ii.rb
  - test_468_validate_ip_address.rb
  - test_46_permutations.rb
  - test_474_ones_and_zeroes.rb
  - test_48_rotate_image.rb
  - test_49_group_anagrams.rb
  - test_503_next_greater_element_ii.rb
  - test_508_most_frequent_subtree_sum.rb
  - test_513_find_bottom_left_tree_value.rb
  - test_515_find_largest_value_in_each_tree_row.rb
  - test_516_longest_palindromic_subsequence.rb
  - test_523_continuous_subarray_sum.rb
  - test_524_longest_word_in_dictionary_through_deleting.rb
  - test_535_encode_and_decode_tinyurl.rb
  - test_538_convert_bst_to_greater_tree.rb
  - test_53_maximum_subarray.rb
  - test_54_spiral_matrix.rb
  - test_556_next_greater_element_iii.rb
  - test_55_jump_game.rb
  - test_560_subarray_sum_equals_k.rb
  - test_56_merge_intervals.rb
  - test_57_insert_interval.rb
  - test_581_shortest_unsorted_continuous_subarray.rb
  - test_59_spiral_matrix_ii.rb
  - test_5_longest_palindromic_substring.rb
  - test_606_construct_string_from_binary_tree.rb
  - test_609_find_duplicate_file_in_system.rb
  - test_61_rotate_list.rb
  - test_621_task_scheduler.rb
  - test_622_design_circular_queue.rb
  - test_623_add_one_row_to_tree.rb
  - test_62_unique_paths.rb
  - test_641_design_circular_deque.rb
  - test_647_palindromic_substrings.rb
  - test_648_replace_words.rb
  - test_652_find_duplicate_subtrees.rb
  - test_654_maximum_binary_tree.rb
  - test_659_split_array_into_consecutive_subsequences.rb
  - test_662_maximum_width_of_binary_tree.rb
  - test_669_trim_a_binary_search_tree.rb
  - test_677_map_sum_pairs.rb
  - test_678_valid_parenthesis_string.rb
  - test_687_longest_univalue_path.rb
  - test_692_top_k_frequent_words.rb
  - test_701_insert_into_a_binary_search_tree.rb
  - test_707_design_linked_list.rb
  - test_713_subarray_product_less_than_k.rb
  - test_71_simplify_path.rb
  - test_720_longest_word_in_dictionary.rb
  - test_725_split_linked_list_in_parts.rb
  - test_729_my_calendar_i.rb
  - test_735_asteroid_collision.rb
  - test_739_daily_temperatures.rb
  - test_74_search_a_2d_matrix.rb
  - test_75_sort_colors.rb
  - test_763_partition_labels.rb
  - test_784_letter_case_permutation.rb
  - test_78_subsets.rb
  - test_797_all_paths_from_source_to_target.rb
  - test_7_reverse_integer.rb
  - test_814_binary_tree_pruning.rb
  - test_817_linked_list_components.rb
  - test_823_binary_trees_with_factors.rb
  - test_82_remove_duplicates_from_sorted_list_ii.rb
  - test_841_keys_and_rooms.rb
  - test_852_peak_index_in_a_mountain_array.rb
  - test_856_score_of_parentheses.rb
  - test_858_mirror_reflection.rb
  - test_863_all_nodes_distance_k_in_binary_tree.rb
  - test_865_smallest_subtree_with_all_the_deepest_nodes.rb
  - test_869_reordered_power_of_2.rb
  - test_86_partition_list.rb
  - test_880_decoded_string_at_index.rb
  - test_889_construct_binary_tree_from_preorder_and_postorder_traversal.rb
  - test_890_find_and_replace_pattern.rb
  - test_894_all_possible_full_binary_trees.rb
  - test_8_string_to_integer_atoi.rb
  - test_901_online_stock_span.rb
  - test_910_smallest_range_ii.rb
  - test_912_sort_an_array.rb
  - test_916_word_subsets.rb
  - test_919_complete_binary_tree_inserter.rb
  - test_921_minimum_add_to_make_parentheses_valid.rb
  - test_92_reverse_linked_list_ii.rb
  - test_937_reorder_data_in_log_files.rb
  - test_946_validate_stack_sequences.rb
  - test_950_reveal_cards_in_increasing_order.rb
  - test_951_flip_equivalent_binary_trees.rb
  - test_958_check_completeness_of_a_binary_tree.rb
  - test_95_unique_binary_search_trees_ii.rb
  - test_967_numbers_with_same_consecutive_differences.rb
  - test_96_unique_binary_search_trees.rb
  - test_973_k_closest_points_to_origin.rb
  - test_979_distribute_coins_in_binary_tree.rb
  - test_981_time_based_key_value_store.rb
  - test_985_sum_of_even_numbers_after_queries.rb
  - test_988_smallest_string_starting_from_leaf.rb
  - test_98_validate_binary_search_tree.rb
  - test_998_maximum_binary_tree_ii.rb
  - test_99_recover_binary_search_tree.rb
- test_helper.rb
.gitignore
.rubocop.yml
Gemfile
README.md
Rakefile
leetcode-ruby.gemspec

test_647_palindromic_substrings.rb

2024-12-17 v. 7.3.6: added "647. Palindromic Substrings"

Dec 17, 2024

244e115 · Dec 17, 2024