Practiced Problems List Tags/Topics arrays, sorting, two-pointers, sliding-window, hashing, hash-table, kadens Arrays https://leetcode.com/problems/valid-mountain-array/description/ Easy https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/ Medium Two Pointers https://leetcode.com/problems/rotate-array/description/ Medium Two Pointers Strings https://leetcode.com/problems/valid-anagram/description/ Easy