n, k = map(int, input().split())
pd = [list(map(int, input().split())) for _ in range(n)]
pd.sort()
dp = [[0] * 2 for _ in range(k + 1)]
for p, d in pd:
    for j in range(k, p - 1, -1):
        dp[j][0] = max(dp[j][0], dp[j][1] + d)
        dp[j][1] = max(dp[j][1], dp[j - p][0] + d)
    for j in range(p - 1, -1, -1):
        dp[j][0] = max(dp[j][0], dp[j][1] + d)

ans = max(v for _, v in dp)
print(ans)