# # 输入样例
N, V = map(int,input().split())   # N表示物品组数，V表示背包容量

v_arr = [[] for i in range(N)]
w_arr = [[] for i in range(N)]
s_arr = []    # 存储每组物品数量


for i in range(N):
    s_arr.append(int(input().strip()))
    for j in range(s_arr[i]):
        in_li = list(map(int, input().split()))
        v_arr[i].append(in_li[0])
        w_arr[i].append(in_li[1])

dp = [0 for i in range(V+1)]    # 出错，范围是[0,V],而不是[0,N]

for i in range(1,N+1):
    for j in range(V,0,-1):
        for s in range(s_arr[i-1]):
            if j>=v_arr[i-1][s-1]:
                dp[j] = max(dp[j], dp[j-v_arr[i-1][s-1]] + w_arr[i-1][s-1])

print(dp[-1])