n,m,k = map(int, input().split())
a = [list(map(int, input().split())) for _ in range(n)]
mask = (1<<k+1) - 1
c = 1
for b in a:
    r = 0
    for x in b: r |= c << x
    r &= mask
    if not r: print(-1); break
    c = r
else: print(k - c.bit_length() + 1)