import collections,sys,math,functools,operator,itertools,bisect,heapq,decimal,string,time,random
#sys.setrecursionlimit(10**9)
#sys.set_int_max_str_digits(0)
n,m,q = map(int,input().split())
item = [list(map(int,input().split())) for i in range(n)]
ans = 0
asu = [0 for i in range(1<<n)]
for s in range(1<<n):
    a,b = 0,0
    for j in range(n):
        if (s >> j) & 1 == 1:
            a += item[j][0]
            b += item[j][1]
    if a <= q:
        asu[s] = b

#or convolution andにする場合は配列をreverseしてからゼータ変換して点積をとってメビウス変換してreverseする
def subset_zeta_transform(s):
    for i in range(n):
        for j in range(1<<n):
            if (j >> i) & 1 == 0:
                s[j | (1 << i)] = max(s[j],s[j | (1 << i)])
    return s
asu = subset_zeta_transform(asu)

for s in range(1<<n):
    a,b = 0,0
    r = 0
    for j in range(n):
        if (s >> j) & 1 == 1:
            a += item[j][0]
            b += item[j][1]
        else:
            r += (1 << j)
    if a <= m:
        ans = max(ans,b + asu[r])
print(ans)