擅长:python、mysql、java
<p>使用Python:</p>
<pre><code>import re
seq="atcttgttcaatggccgatcaacggtcgacaatcaa"
D = [ c for c in seq ]
with open("input") as f:
for line in f:
line=line.rstrip('\n')
if re.match(".{20}aacg", line):
cnt = sum([ 1 for c,d in zip(line,D) if c != d])
if cnt < 4:
print cnt, line
</code></pre>