NOI '19 P1 - Route
View as PDFIn Byteland's train station, there are  stations and 
 trains in total. For each train, it will start from station 
 at the moment 
 and arrive at station 
 at the moment 
. Note that we can only take the train 
 at the moment 
 as well as get off at the moment 
.
Starting from station , Kevin is going to station 
 by train. To reach his destination, he can do multiple transfers. Specifically, we can transfer from train 
 to train 
 if 
 and 
. In this case, Kevin will have to wait for 
 moments and take train 
 at the moment 
.
Let's evaluate Kevin's unhappiness as the value .
Each time when Kevin has to wait for  moments in a transfer process, 
 will be increased by 
 (
 are three given constraints). Specifically, we consider the process between the moment 
 and the moment getting on the first train also as a transfer, which means the waiting time needs to be taken into account.
Secondly, if Kevin reaches station  at the moment of 
, 
 will be increased by 
.
Please minimize Kevin's unhappiness value . We guarantee that there is at least one possible plan to arrive at station 
.
Input Specification
The first line contains  integers 
.
For the following  lines, each line contains 
, indicating the information of train 
.
Constraints
All of the test cases satisfy , 
, 
, 
, 
, 
, 
.
| Test Case | Others | |||
|---|---|---|---|---|
| 1~2 | None | |||
| 3~4 | ||||
| 5~8 | ||||
| 9 | ||||
| 10 | ||||
| 11~14 | None | None | ||
| 15 | ||||
| 16~17 | ||||
| 18~20 | None | 
Output Specification
Please output an integer on one line, indicating the minimum possible value of .
Sample Input 1
3 4 1 5 10
1 2 3 4
1 2 5 7
1 2 6 8
2 3 9 10
Sample Output 1
94
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