擅长:python、mysql、java
<p>这是我对同一个问题(玛纳萨和子序列)的意见。
<a href="https://www.hackerrank.com/contests/infinitum-may14/challenges/manasa-and-sub-sequences" rel="nofollow">https://www.hackerrank.com/contests/infinitum-may14/challenges/manasa-and-sub-sequences</a></p>
<p>我希望这能帮助你想出更好的办法。在</p>
<pre><code>ans = 0
count = 0
for item in raw_input():
temp = (ans * 10 + (count + 1)*(int(item)))%1000000007
ans = (ans + temp)%1000000007
count = (count*2 + 1)%1000000007
print ans
</code></pre>