from itertools import product
import sys
#input = sys.stdin.readline
def inpl(): return list(map(int, input().split()))

N, M, K = inpl()
A = [inpl() for _ in range(N)]
ans = -1
for J in product(range(M), repeat=N):
    tmp = 0
    for i, j in enumerate(J):
        tmp += A[i][j]
    if tmp <= K:
        ans = max(ans, tmp)

print(K-ans if ans >= 0 else -1)