<pre><code>def main():
x = {}
for word in sentence:
x[word] = sentence.count(word)
for letter in sorted(x):
print (letter + ': ' + str(x[letter]))
sentence=input("Enter a sentence: ")
main()
</code></pre>
<p>这段代码输出了字母和它被使用了多少次,但是我如何修改它来找到和打印最常用的字母呢?你知道吗</p>