擅长:python、mysql、java
<p>你可以试试这个:</p>
<pre><code>s = 'Python is good prototyping language'
seen = []
new_s = ''
for i in s:
if i not in seen:
new_s += i
seen.append(i)
else:
if i != ' ':
new_s += "@"
else:
new_s += ' '
</code></pre>
<p>输出:</p>
<pre><code>'Python is g@@d pr@@@@@@@@@ la@@u@@e'
</code></pre>
<p>偶数分拣机解决方案:</p>
<pre><code>new_s = ''.join('@' if a in s[:i] and a != ' ' else a for i, a in enumerate(s))
</code></pre>
<p>输出:</p>
<pre><code>'Python is g@@d pr@@@@@@@@@ la@@u@@e'
</code></pre>