import sys
from math import sqrt, pi, sin
inp = lambda : sys.stdin.readline()[:-1]
mii = lambda x = " ": [*map(int,inp().split(x))]
mfi = lambda x = " ": [*map(float,inp().split(x))]
ii = lambda : int(inp())
for _ in range(ii()):
n, m = mii()
l = [mii() for i in range(n)]
d = [0] + mii()
ans = 0
for i in range(n):
k, *l2, cost = l[i]
mn = min([d[i] for i in l2])
ans += mn * cost
print(ans)