from heapq import *
import sys

sys.setrecursionlimit(10 ** 6)
int1 = lambda x: int(x) - 1
p2D = lambda x: print(*x, sep="\n")
def MI(): return map(int, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]

# 食べるピザを確定させたとき、値段の高い順に有料、無料を繰り返すのが最適
# よって、値段の高い順にピザを見ていって、次が有料→次が無料→次が有料→次が無料と
# 表を交互に遷移させる
def main():
    n, k = MI()
    hp = []
    for _ in range(n):
        p, d = MI()
        heappush(hp, [-p, d])
    # dp0[i] i円で得られる最大のおいしさ（次のピザ有料）
    # dp1[i] i円で得られる最大のおいしさ（次のピザ無料）
    dp0 = [-1] * (k + 1)
    dp1 = [-1] * (k + 1)
    dp0[0] = 0
    while hp:
        p, d = heappop(hp)
        p = -p
        for i in range(k, -1, -1):
            if i + p <= k and dp0[i] != -1:
                dp1[i + p] = max(dp1[i + p], dp0[i] + d)
            if dp1[i] != -1:
                dp0[i] = max(dp0[i], dp1[i] + d)
    print(max(max(dp0), max(dp1)))

main()