def or_convolution(A, B, MOD=-1):
    n = max(len(A), len(B))
    l = (n - 1).bit_length()
    n = 1 << l
    A += [0] * (n - len(A))
    B += [0] * (n - len(B))

    def f(A):
        for i in range(l):
            for bit in range(n):
                if bit >> i & 1:
                    A[bit] += A[bit ^ (1 << i)]
                    if MOD != -1:
                        A[bit] %= MOD

    def invf(A):
        for i in range(l):
            for bit in range(n):
                if bit >> i & 1:
                    A[bit] -= A[bit ^ (1 << i)]
                    if MOD != -1:
                        A[bit] %= MOD

    f(A)
    f(B)
    if MOD != -1:
        C = [a * b % MOD for a, b in zip(A, B)]
    else:
        C = [a * b for a, b in zip(A, B)]
    invf(C)
    return C


n, m, q = map(int, input().split())
assert 1 <= n <= 20
assert 1 <= m <= 10**9
assert 1 <= q <= 10**9

A = [0] * n
B = [0] * n
for i in range(n):
    a, b = map(int, input().split())
    assert 1 <= a <= 10**9
    assert 1 <= b <= 10**9

    A[i] = a
    B[i] = b

C = [0] * (1 << n)
W = [0] * (1 << n)
for bit in range(1 << n):
    for i in range(n):
        if bit >> i & 1:
            C[bit] = C[bit - (1 << i)] + A[i]
            W[bit] = W[bit - (1 << i)] + B[i]
            break

X = [0] * (1 << n)
Y = [0] * (1 << n)
for bit in range(1 << n):
    if C[bit] <= m:
        X[bit] = 1
    if C[bit] <= q:
        Y[bit] = 1

Z = or_convolution(X, Y)
ans = 0
for bit in range(1 << n):
    if Z[bit] > 0 and W[bit] > ans:
        ans = W[bit]

print(ans)