import collections 
N, V = map(int, input().split())
v = collections.defaultdict(list)
w = collections.defaultdict(list)

for i in range(N):
    m = int(input())
    for _ in range(m):
        a, b = map(int, input().split())
        v[i].append(a)
        w[i].append(b)

dp = [0 for i in range(V+1)]
for i in range(N):
    for j in range(V, -1, -1):
        for k in range(len(v[i])):
            if j >= v[i][k]:
                dp[j] = max(dp[j-v[i][k]]+w[i][k], dp[j])
print(max(dp))