import sys

# sys.setrecursionlimit(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()
dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
inf = (1 << 63)-1
# inf = (1<<31)-1
md = 10**9+7
# md = 998244353

n, k = LI()
pd = LLI(n)
pd.sort(key=lambda x: -x[0])

dp0 = [-1]*(k+1)
dp1 = [-1]*(k+1)
dp0[0] = 0
for p, d in pd:
    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)

ans = max(max(dp0), max(dp1))
print(ans)