6153：A Secret

题目描述

Today is the birthday of SF,so VS gives two strings S1,S2 to SF as a present,which have a big secret.SF is interested in this secret and ask VS how to get it.There are the things that VS tell:
Suffix(S2,i) = S2[i...len].Ni is the times that Suffix(S2,i) occurs in S1 and Li is the length of Suffix(S2,i).Then the secret is the sum of the product of Ni and Li.
Now SF wants you to help him find the secret.The answer may be very large, so the answer should mod 1000000007.

输入解释

Input contains multiple cases.
  The first line contains an integer T,the number of cases.Then following T cases.
  Each test case contains two lines.The first line contains a string S1.The second line contains a string S2.
  1<=T<=10.1<=|S1|,|S2|<=1e6.S1 and S2 only consist of lowercase ,uppercase letter.

输出解释

For each test case,output a single line containing a integer,the answer of test case.
The answer may be very large, so the answer should mod 1e9+7.

输入样例

2
aaaaa
aa
abababab
aba

输出样例

13
19

提示

case 2: 
Suffix(S2,1) = "aba",
Suffix(S2,2) = "ba",
Suffix(S2,3) = "a".
N1 = 3,
N2 = 3,
N3 = 4.
L1 = 3,
L2 = 2,
L3 = 1.
ans = （3*3+3*2+4*1）%1000000007.

来自杭电HDUOJ的附加信息

Recommend

liuyiding

该题目是Virtual Judge题目，来自杭电HDUOJ

题目来源 2017中国大学生程序设计竞赛 - 网络选拔赛

源链接： HDU-6153

最后修改于 2020-10-25T23:28:50+00:00 由爬虫自动更新

共提交 0 次

通过率 --%

时间上限	内存上限
2000/1000MS(Java/Others)	256000/256000K(Java/Others)