diff --git a/roman_numeral/Makefile b/13_roman_numeral/Makefile
similarity index 100%
rename from roman_numeral/Makefile
rename to 13_roman_numeral/Makefile
diff --git a/roman_numeral/roman_numeral.c b/13_roman_numeral/roman_numeral.c
similarity index 100%
rename from roman_numeral/roman_numeral.c
rename to 13_roman_numeral/roman_numeral.c
diff --git a/lru_cache/lru_cache.c b/146_lru_cache/lru_cache.c
similarity index 100%
rename from lru_cache/lru_cache.c
rename to 146_lru_cache/lru_cache.c
diff --git a/lru_cache/lru_cache_unsoluted.c b/146_lru_cache/lru_cache_unsoluted.c
similarity index 100%
rename from lru_cache/lru_cache_unsoluted.c
rename to 146_lru_cache/lru_cache_unsoluted.c
diff --git a/lru_cache/lru_cache_without_list.c b/146_lru_cache/lru_cache_without_list.c
similarity index 100%
rename from lru_cache/lru_cache_without_list.c
rename to 146_lru_cache/lru_cache_without_list.c
diff --git a/letter_combinations_of_a_phone_number/Makefile b/17_letter_combinations_of_a_phone_number/Makefile
similarity index 100%
rename from letter_combinations_of_a_phone_number/Makefile
rename to 17_letter_combinations_of_a_phone_number/Makefile
diff --git a/letter_combinations_of_a_phone_number/letter_combinations.c b/17_letter_combinations_of_a_phone_number/letter_combinations.c
similarity index 100%
rename from letter_combinations_of_a_phone_number/letter_combinations.c
rename to 17_letter_combinations_of_a_phone_number/letter_combinations.c
diff --git a/two_sum/two_sum.c b/1_two_sum/two_sum.c
similarity index 100%
rename from two_sum/two_sum.c
rename to 1_two_sum/two_sum.c
diff --git a/longest_substring_without_repeat/Makefile b/3_longest_substring_without_repeat/Makefile
similarity index 100%
rename from longest_substring_without_repeat/Makefile
rename to 3_longest_substring_without_repeat/Makefile
diff --git a/longest_substring_without_repeat/longest_substring_without_repeat.c b/3_longest_substring_without_repeat/longest_substring_without_repeat.c
similarity index 100%
rename from longest_substring_without_repeat/longest_substring_without_repeat.c
rename to 3_longest_substring_without_repeat/longest_substring_without_repeat.c
diff --git a/median_of_two_sorted_array/Makefile b/4_median_of_two_sorted_array/Makefile
similarity index 100%
rename from median_of_two_sorted_array/Makefile
rename to 4_median_of_two_sorted_array/Makefile
diff --git a/median_of_two_sorted_array/median_of_two_sorted_array.c b/4_median_of_two_sorted_array/median_of_two_sorted_array.c
similarity index 100%
rename from median_of_two_sorted_array/median_of_two_sorted_array.c
rename to 4_median_of_two_sorted_array/median_of_two_sorted_array.c
diff --git a/n_queens/Makefile b/51_n_queens/Makefile
similarity index 100%
rename from n_queens/Makefile
rename to 51_n_queens/Makefile
diff --git a/n_queens/n_queens.c b/51_n_queens/n_queens.c
similarity index 100%
rename from n_queens/n_queens.c
rename to 51_n_queens/n_queens.c
diff --git a/longest_palindromic_substring/Makefile b/5_longest_palindromic_substring/Makefile
similarity index 100%
rename from longest_palindromic_substring/Makefile
rename to 5_longest_palindromic_substring/Makefile
diff --git a/longest_palindromic_substring/longest_palindromic_substring.c b/5_longest_palindromic_substring/longest_palindromic_substring.c
similarity index 100%
rename from longest_palindromic_substring/longest_palindromic_substring.c
rename to 5_longest_palindromic_substring/longest_palindromic_substring.c
diff --git a/atoi/atoi.c b/8_atoi/atoi.c
similarity index 100%
rename from atoi/atoi.c
rename to 8_atoi/atoi.c