n,k = map(int,input().split())
dp = [0]*n
a = [0]*n
g = [[] for _ in range(n)]

for i in range(n):
    a[i],_ = map(int,input().split())
    *b, = map(int,input().split())
    for bi in b:
        bi -= 1
        if bi < i: g[bi].append(i)

for i in range(n):
    if i: dp[i] = max(dp[i],dp[i-1])
    for v in g[i]:
        dp[v] = max(dp[v],dp[i]-a[i]+a[v])
print(dp[-1])