Function directedmst 

pub fn directedmst(reader: impl Read, writer: impl Write)

✅ AC 83ms

problem here

Detail

Case Name	Status	Exec Time
example_00	AC	0 ± 0 ms
example_01	AC	0 ± 0 ms
random_00	AC	44 ± 3 ms
random_01	AC	54 ± 4 ms
random_02	AC	39 ± 1 ms
random_03	AC	67 ± 6 ms
random_04	AC	22 ± 1 ms
max_random_00	AC	71 ± 4 ms
max_random_01	AC	69 ± 3 ms
max_random_02	AC	75 ± 4 ms
max_random_03	AC	83 ± 4 ms
max_random_04	AC	79 ± 5 ms