Submission #19218163

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Source Code Expand

from sys import stdin 
def input():
    return stdin.readline()

n,m = map(int,input().split())
g = [[] for i in range(n)]
for i in range(1,n):
    p = int(input())
    g[p].append(i)
val = [0 for i in range(n+1)]
for i in range(m):
    b,c = map(int,input().split())
    val[b] = c
for i in range(n):
    q = []
    for j in g[0]:
        q.append(j)
    while q:
        idx = q.pop()
        if g[idx]:
            temp = 2**63 
            for j in g[idx]:
                if val[j]<temp:
                    temp = val[j]
            val[idx] += temp 
            #print(idx,temp)
            for j in g[idx]:
                val[j] -= temp
                q.append(j)
print(sum(val))
#print(g)

Submission Info

Judge Result