n,m,k = map(int,input().split())
sur_list = []
diff_list = []
diff_plus_list = []
conv_bin_list = []
for i in range(n):
    sur_list.append(list(map(int,input().split())))
first_row = 0
for i in range(n):
    first_row += sur_list[i][0]
if first_row > k:
    print("-1")
    exit()
for i in range(n):
    for j in range(1,m):
        diff_list.append(sur_list[i][j] - sur_list[i][0])
for i in range(2 ** (n*(m-1))):
    conv_bin = bin(i)
    conv_bin_list.append(conv_bin[2::].zfill(n))
for i in range(len(conv_bin_list)):
    tar_conv = conv_bin_list[i]
    price = 0
    for j in range(n):
        price += int(tar_conv[j]) * diff_list[j]
    diff_plus_list.append(price)
for i in range(k - first_row, 0, -1):
    if i in diff_plus_list:
        print(k - (first_row + i))
        exit()
print(k - first_row)