N, K = map(int, input().split())
inf = 10 ** 18
pre0 = [-inf] * (K + 1)
pre1 = [-inf] * (K + 1)
pre0[0] = 0
S = []
for _ in range(N):
    P, D = map(int, input().split())
    S.append((-P, -D))
S.sort()

for P, D in S:
    P, D = -P, -D
    dp0 = [-inf] * (K + 1)
    dp1 = [-inf] * (K + 1)
    for i in range(K + 1):
        dp0[i] = max(dp0[i], pre0[i], pre1[i] + D)
        dp1[i] = max(dp1[i], pre1[i])
        if i - P >= 0:
            dp1[i] = max(dp1[i], pre0[i - P] + D)
    dp0, pre0 = pre0, dp0
    dp1, pre1 = pre1, dp1

print(max(pre0 + pre1))