n, i = map(int, input().split())
DP = [[-1 for _ in range(i + 1)] for _ in range(n + 1)]
DP[0][0] = 0
for j in range(n):
    s, a = map(int, input().split())
    for x in range(i + 1):
        if DP[j][x] != -1:
            DP[j + 1][x] = max(DP[j + 1][x], DP[j][x])
            if x + s <= i:
                DP[j + 1][x + s] = max(DP[j + 1][x + s], DP[j][x] + a)
print(max(DP[n]))