Laskettelukeskus

n = int(input())
slopesUP = [[] for i in range(n + 1)]
slopesDOWN = [[] for i in range(n + 1)]

for i in range(n - 1):
    a, b = map(int, input().split())
    slopesDOWN[a].append(b)
    slopesUP[b].append(a)

snowplows = list(map(int, input().split()))
vertailuarvo=snowplows[0]
snowplows[0]=0
def go_thru(slopehti):
    lehtiarvo = snowplows[slopehti - 1]
    slope = slopehti
    snowplows[slopehti - 1] = 0
    juuriarvo = snowplows[0]
    while slope != 1:
        slope = slopesUP[slope][0]###
        if lehtiarvo>0:
            snowplows[slope - 1] -= lehtiarvo


lehtilista = [i for i in range(2, n + 1)]
while len(lehtilista) > 0:
    for lehti in lehtilista:
        # onko nykylehti
        if slopesDOWN[lehti] == []:
            go_thru(lehti)
            lehtilista.remove(lehti)
            slopesDOWN[slopesUP[lehti][0]].remove(lehti)

print(max(abs(snowplows[0]),vertailuarvo))

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 5

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 6

Group: 1, 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 8

Group: 1, 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 10

Group: 1, 2

Verdict: ACCEPTED

Test 11

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 1, 2

Verdict: ACCEPTED

Test 13

Group: 2

Verdict: TIME LIMIT EXCEEDED