import sys
input = sys.stdin.buffer.readline
sys.setrecursionlimit(10 ** 7)


def pop_count(T):
    T = (T & 0x55555555) + ((T >> 1) & 0x55555555)
    T = (T & 0x33333333) + ((T >> 2) & 0x33333333)
    T = (T & 0x0F0F0F0F) + ((T >> 4) & 0x0F0F0F0F)
    T = (T & 0x00FF00FF) + ((T >> 8) & 0x00FF00FF)
    T = (T & 0x0000FFFF) + ((T >> 16) & 0x0000FFFF)
    return T


N, M = map(int, input().split())
A = tuple(tuple(map(int, input().split())) for _ in range(N))
row = [sum(a) for a in A]
col = [sum(a) for a in zip(*A)]
# row += [sum(A[i][i] for i in range(N))]
# row += [sum(A[N-i-1][i] for i in range(N))]


ans = 10**18
n = N + 2
for S in range(1 << n):
    p = pop_count(S)
    if N + p < M:
        continue
    tmp = 0
    coltmp = col[:]
    for i in range(N):
        if (S >> i) & 1:
            tmp += row[i]
            for j in range(N):
                coltmp[j] -= A[i][j]
    if (S >> N) & 1:
        for i in range(N):
            if (S >> i) & 1:
                continue
            tmp += A[i][i]
            coltmp[i] -= A[i][i]
    if (S >> (N + 1)) & 1:
        for i in range(N):
            if (S >> i) & 1:
                continue
            tmp += A[i][N-i-1]
            coltmp[i] -= A[i][N-i-1]
    if N % 2 == 1:
        m = N // 2
        if ~(S >> m) & 1 and (S >> N) & 1 and (S >> (N + 1)) & 1:
            tmp -= A[m][m]
            coltmp[m] += A[m][m]

    coltmp.sort()
    tmp += sum(coltmp[:M-p])
    ans = min(ans, tmp)

print(ans)