file = open("rucsac.in", "r")
N, G = map(int, file.readline().split())
v = []
for _ in range(N):
	c, p = map(int, file.readline().split())
	v.append([c, p])

pd = [(0 for _ in range(G+1)) for __ in range(N+1)]

for n in range(N):
	for g in range(1, G+1):
		pd[n][g] = -1
		if n > 0:
			pd[n][g] = pd[n-1][g]
		if g >= v[n][0]:
			pd[n][g] = max(pd[n][g], v[n][1]+pd[n-1][g-v[n][1]])

print(pd[N-1][G])