7 人解决，10 人已尝试。
8 份提交通过，共有 20 份提交。
6.6 EMB 奖励。
单点时限: 2.0 sec
内存限制: 256 MB
Farmer John has grown so lazy that he no longer wants to continue
maintaining the cow paths that currently provide a way to visit
each of his N (5 <= N <= 10,000) pastures (conveniently numbered
1..N). Each and every pasture is home to one cow. FJ plans to remove
as many of the P (N-1 <= P <= 100,000) paths as possible while keeping
the pastures connected. You must determine which N-1 paths to keep.
Bidirectional path j connects pastures S_j and E_j (1 <= S_j <= N;1 <= E_j <= N; S_j != E_j) and requires L_j (0 <= L_j <= 1,000) time to traverse. No pair of pastures is directly connected by more than one path.
The cows are sad that their transportation system is being reduced. You must visit each cow at least once every day to cheer her up. Every time you visit pasture i (even if you’re just traveling through), you must talk to the cow for time C_i (1 <= C_i <= 1,000).
You will spend each night in the same pasture (which you will choose) until the cows have recovered from their sadness. You will end up talking to the cow in the sleeping pasture at least in the morning when you wake up and in the evening after you have returned to
sleep.
Assuming that Farmer John follows your suggestions of which paths to keep and you pick the optimal pasture to sleep in, determine the minimal amount of time it will take you to visit each cow at least once in a day.
Line 1: Two space-separated integers: N and P
Lines 2..N+1: Line i+1 contains a single integer: C_i
Lines N+2..N+P+1: Line N+j+1 contains three space-separated
integers: S_j, E_j, and L_j
cows (including the two visits to the cow in your
sleeping-pasture)
5 7 10 10 20 6 30 1 2 5 2 3 5 2 4 12 3 4 17 2 5 15 3 5 6 4 5 12
176
7 人解决，10 人已尝试。
8 份提交通过，共有 20 份提交。
6.6 EMB 奖励。