COCI '19 Contest 5 #4 Putovanje
View as PDFLittle Fabijan loves bars and travels. He wishes to drink beer coffee in each of the  towns in his country
conveniently numbered from 
 to 
. The towns are connected via 
 bidirectional roads such that
each town is reachable from any other town by traversing some of the roads. Fabijan decided to drink
coffee in every town in order from town number 
 to town number 
. Therefore, he starts from town
number 
 (where he drinks his first coffee) and travels to town number 
 for his next cup of coffee. During
that travel, he might pass through a number of different towns but he won't make a coffee stop in those
towns. After drinking coffee in town 
, he will proceed to travel to town 
, and so on until he finally
reaches town 
 where he will drink his last coffee.
In order to traverse a certain road, he needs to have a valid ticket. The -th road can be traversed if you
have either a single-pass ticket which costs 
 euros or a multi-pass ticket which costs 
 euros. For
each road, Fabijan can decide to buy a single-pass ticket each time he needs to traverse that road or he
might opt to buy a multi-pass ticket once.
Write a program that computes the smallest number of euros Fabijan needs to spend on tickets in order to successfully complete his travels.
Input
The first line contains an integer  
 from the task description.
In -th of the next 
 lines there are four integers 
which represent that towns 
 and 
 are connected with a road with ticket prices 
 and 
.
Output
In a single line output the smallest cost of travel.
Scoring
| Subtask | Score | Constraints | 
|---|---|---|
| Each town will be directly connected with at most two other towns. | ||
| No additional constraints. | 
Sample Input 1
4
1 2 3 5
1 3 2 4
2 4 1 3
Sample Output 1
10
Explanation for Sample Output 1
Fabijan first travels from town  to town 
 and it is optimal for him to buy a multi-pass ticket (
 euros)
for the road which connects them. Then he travels from town 
 to town 
 via town 
. He already has a
multi-pass ticket that takes him from 
 to 
 and he buys a single-pass ticket from town 
 to town 
 (
euros). On his travels from town 
 to town 
 he buys another single-pass ticket that takes him from town
 back to town 
 (
 euros) and after that buys a single-pass ticket that takes him from town 
 to town 
(
 euro). In total, he spent 
 euros.
Sample Input 2
4
1 4 5 5
3 4 4 7
2 4 2 6
Sample Output 2
16
Sample Input 3
5
1 2 2 3
1 3 2 3
1 4 2 3
1 5 2 3
Sample Output 3
11
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