@@ -0,0 +1,210 @@
+package com.example.yin_zeping.myapplication;%0A%0A/**%0A * Created by yin_zeping on 2016/3/1.%0A */%0Apublic class StringUtils %7B%0A%0A    public static String subString(String s) %7B%0A        return s.substring(0, 2);%0A    %7D%0A%7D%0A

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