"""

"""

N,M,Q = map(int,input().split())

A = []
B = []

for i in range(N):
    a,b = map(int,input().split())
    A.append(a)
    B.append(b)

# dpM[s] = 集合sの部分集合において、M円で購入できる最高の価値
# を高速ゼータ変換で計算する

dpM = [0] * (2**N)
for bit in range(2**N):
    asum = 0
    bsum = 0
    for i in range(N):
        if 2**i & bit:
            asum += A[i]
            bsum += B[i]
    if asum <= M:
        dpM[bit] = bsum

#高速ゼータ変換
for bit in range(2**N):
    for i in range(N):
        if 2**i | bit != bit:
            dpM[2**i | bit] = max(dpM[2**i | bit] , dpM[bit])


# 同様にdpQも計算する
# dpQ[s] = 集合sの部分集合において、Q円で購入できる最高の価値

dpQ = [0] * (2**N)
for bit in range(2**N):
    asum = 0
    bsum = 0
    for i in range(N):
        if 2**i & bit:
            asum += A[i]
            bsum += B[i]
    if asum <= Q:
        dpQ[bit] = bsum

#高速ゼータ変換
for bit in range(2**N):
    for i in range(N):
        if 2**i | bit != bit:
            dpQ[2**i | bit] = max(dpQ[2**i | bit] , dpQ[bit])


# 答を計算
ans = 0
for bit in range(2**N):
    rembit = (2**N-1) ^ bit
    ans = max(ans , dpM[bit] + dpQ[rembit])

print (ans)