Little 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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