Intermediate · Dictionaries · 137 of 264
Group by first letter
Group words by their first letter. Print the letters in alphabetical order; after each, the words in the order they came.
Input: one line of words in small letters. Output: lines like a: apple avocado
Examples
Input
apple banana avocado cherry blueberry
Output
a: apple avocado b: banana blueberry c: cherry
Input
one
Output
o: one
One more test checks other inputs when you press Check.
Stuck? The idea behind dictionaries
A dictionary links keys to values, like words to meanings: ages["Ann"] = 12. Looking up a key is fast, however big it is.
.get(key, 0) gives a default when the key isn't there; looping over a dictionary gives its keys, .items() gives keys and values together.
counts = {}
for word in input().split():
counts[word] = counts.get(word, 0) + 1
for word, n in counts.items():
print(word, n)Watch for: Reading a key that isn't there stops the program with a KeyError: check with in, or use .get().