le="position: relative; overflow: hidden;"><div class=content><p><span style="font-size: medium">一个字符串S,长度&lt;=10^6</span></p></div></div></div></div></div><div class="row"><div class="column"><h4 class="ui top attached block header">输出格式</h4><div class="ui bottom attached segment font-content"><div style="position: relative; overflow: hidden;"><div class=content><p><font size="4">输出答案Mod10^9+7</font></p></div></div></div></div></div><div class="row"><div class="column"><h4 cla