import sys

sys.setrecursionlimit(200005)
# sys.set_int_max_str_digits(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-(-1 << 31)
inf = -1-(-1 << 62)

# md = 10**9+7
md = 998244353

n,m,q=LI()
pv=LLI(n)

sp=sv=0
for p,v in pv:
    sp+=p
    sv+=v

pp=[0]*(1<<n)
vv=[0]*(1<<n)
dp=[-inf]*(1<<n)
if sp<=q:dp[0]=sv
for s in range(1,1<<n):
    i=s.bit_length()-1
    p,v=pv[i]
    pp[s]=pp[s^1<<i]+p
    vv[s]=vv[s^1<<i]+v
    if sp-pp[s]<=q:dp[s]=sv-vv[s]

k=1
for _ in range(n):
    for s in range(1<<n):
        if s&k:
            ns=s^k
            dp[ns]=max(dp[ns],dp[s])
    k<<=1

ans=0
for s in range(1<<n):
    if pp[s]<=m:
        ans=max(ans,vv[s]+dp[s])

print(ans)