编程介的小学生 2016-11-07 04:07 采纳率: 20.5%
浏览 910
已采纳

Count the string

Description
It is well known that AekdyCoin is good at string problems as well as number theory problems. When given a string s, we can write down all the non-empty prefixes of this string. For example:
s: "abab"
The prefixes are: "a", "ab", "aba", "abab"
For each prefix, we can count the times it matches in s. So we can see that prefix "a" matches twice, "ab" matches twice too, "aba" matches once, and "abab" matches once. Now you are asked to calculate the sum of the match times for all the prefixes. For "abab", it is 2 + 2 + 1 + 1 = 6.
The answer may be very large, so output the answer mod 10007.

Input
The first line is a single integer T, indicating the number of test cases.
For each case, the first line is an integer n (1 <= n <= 200000), which is the length of string s. A line follows giving the string s. The characters in the strings are all lower-case letters.

Output
For each case, output only one number: the sum of the match times for all the prefixes of s mod 10007.

Sample Input
1
4
abab

Sample Output
6

  • 写回答

1条回答 默认 最新

  • threenewbee 2016-11-07 04:05
    关注
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论

报告相同问题?

悬赏问题

  • ¥15 Python时间序列如何拟合疏系数模型
  • ¥15 求学软件的前人们指明方向🥺
  • ¥50 如何增强飞上天的树莓派的热点信号强度,以使得笔记本可以在地面实现远程桌面连接
  • ¥20 双层网络上信息-疾病传播
  • ¥50 paddlepaddle pinn
  • ¥20 idea运行测试代码报错问题
  • ¥15 网络监控:网络故障告警通知
  • ¥15 django项目运行报编码错误
  • ¥15 STM32驱动继电器
  • ¥15 Windows server update services