N,K = map(int, input().split())
L = []
for _ in range(N):
    p,d = map(int, input().split())
    L.append((p, d))

L.sort(reverse=True)
dp0 = [[0]*(K+1) for _ in range(N+1)]
dp1 = [[0]*(K+1) for _ in range(N+1)]
for i in range(N):
    for j in range(K+1):
        if j < L[i][0] and dp1[i][j] > 0:
            dp0[i+1][j] = max(dp0[i][j], dp1[i][j]+L[i][1])
        elif j < L[i][0]:
            dp0[i+1][j] = dp0[i][j]
        else:
            if dp1[i][j] > 0:
                dp0[i+1][j] = max(dp0[i][j], dp1[i][j]+L[i][1])
            else:
                dp0[i+1][j] = dp0[i][j]
            dp1[i+1][j] = max(dp1[i][j], dp0[i][j-L[i][0]]+L[i][1])

print(max(dp0[N][K], dp1[N][K]))