from collections import Counter

with open('sample.txt', 'r') as f:
text = f.read().lower()

counter = Counter(c for c in text if c.isalpha())
total_chars = sum(counter.values())

with open('result.txt', 'w') as f:
f.write(f'共{total_chars}个字符，其中每个字母的分布情况为：\n')
for char, count in sorted(counter.items()):
f.write(f'{char}:{count}, ')