Frequency Counting

Many problems become trivial once you count occurrences. Frequency maps answer questions like "how many of each?" and "what appears most/least?" Building Frequency Maps The basic pattern for counting involves iterating through items and incrementing a counter for each unique value. Find Most Common Element Once you have frequencies, finding the most common element is straightforward. Check Anagrams Two strings are anagrams if they have exactly the same character frequencies. Frequency maps unlock a surprising number of problems beyond simple counting. Once you build the habit of reaching for a dictionary whenever you see "how many" or "which is most common," many problems become almost trivial. In practice, Python provides a built-in shortcut for frequency maps. Frequency maps are one of t