链接:
https://ac.nowcoder.com/acm/contest/57361/A
来源:牛客网
Daniel and sszcdjr are playing a game. The game is played on a sequence 
aaa of length 
nnn. Initially, all elements in 
aaa are equal to 
000. They will do the following operations 
mmm times on it:
* Daniel selects one segment 
[li,ri][l_i,r_i][li,ri] (
1≤l≤r≤n1\le l\le r\le n1≤l≤r≤n);
* Then, sszcdjr chooses a real number 
xxx such that 
0≤x≤10\le x\le 10≤x≤1 \bf{uniformly at random};
* For all 
li≤j≤ril_i\le j\le r_ili≤j≤ri, set 
aj:=aj+xa_j:=a_j+xaj:=aj+x.
However, sszcdjr thinks it is unfair for him. So he adds a rule: for any two segments 
[li,ri][l_i,r_i][li,ri] and 
[lj,rj][l_j,r_j][lj,rj] (
i≠ji\ne ji=j), one of the following condition must holds:
* The two segments are completely disjoint. More formally, either 
li≤ri<lj≤rjl_i\le r_i<l_j\le r_jli≤ri<lj≤rj or 
lj≤rj<li≤ril_j\le r_j<l_i\le r_ilj≤rj<li≤ri;
* One of the two segments are inside another. More formally, either 
li≤lj≤rj≤ril_i\le l_j\le r_j\le r_ili≤lj≤rj≤ri or 
lj≤li≤ri≤rjl_j\le l_i\le r_i\le r_jlj≤li≤ri≤rj.
Note that two segments can be exactly the same.
Let 
sss be the maximum number in 
aaa after the operations. zxx is crazy about probabilities, so he gives you 
ttt queries. In each query, he gives you two numbers 
PPP, 
QQQ, and asks you the probability that 
P≤s≤QP\le s\le QP≤s≤Q. You just need to tell him the answer modulo 
998 244 353998~244~353998 244 353.