Vaqt limiti: 2 sekund
Xotira limiti: 128 MB
Valerian was captured by Shapur. The victory
was such a great one that Shapur decided to carve a
scene of Valerian's defeat on a mountain. So he had to find the best place to
make his victory eternal!
He decided to visit all n cities
of Persia to find the best available mountain, but after the recent war he was
too tired and didn't want to traverse a lot. So he wanted to visit each of
these n cities at least once with smallest
possible traverse. Persian cities are connected with bidirectional roads. You
can go from any city to any other one using these roads and there is a unique
path between each two cities.
All cities are numbered 1 to n. Shapur is
currently in the city 1 and he
wants to visit all other cities with minimum possible traverse. He can finish
his travels in any city.
Help Shapur find how much He should travel.
Input
First line contains a single natural number n (1 ≤ n ≤ 10^{5})
— the amount of cities.
Next n - 1 lines contain 3 integer numbers each x_{i}, y_{i} and w_{i} (1 ≤ x_{i}, y_{i} ≤ n, 0 ≤ w_{i} ≤ 2 × 10^{4}). x_{i} and y_{i} are
two ends of a road and w_{i} is the length of that road.
Output
A single integer number, the minimal length of Shapur's travel.
Samples
№ |
Input |
Output |
1 |
3 |
7 |
2 |
3 |
9 |
Text from: codeforces.ru