import std.conv, std.functional, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.container, std.math, std.numeric, std.range, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


enum INF = 10^^9;

int M, N;
int[][] A;

void main() {
  try {
    for (; ; ) {
      M = readInt();
      N = readInt();
      A = new int[][](M, N);
      foreach (x; 0 .. M) foreach (y; 0 .. N) {
        A[x][y] = readInt();
      }
      
      auto B = new int[M];
      foreach (x; 0 .. M) {
        foreach (y; 0 .. N) {
          B[x] |= A[x][y] << y;
        }
      }
      
      auto ps = new int[][1 << N];
      foreach (p; 0 .. 1 << N) {
        int b;
        foreach (y; 0 .. N) {
          if ((p >> y) & 1) {
            b ^= ((7 << y) >> 1) & ((1 << N) - 1);
          }
        }
        ps[b] ~= p;
      }
      debug {
        writeln(ps.map!"a.length");
      }
      
      auto dp = new int[][][](M + 1, 1 << N, 1 << N);
      foreach (i; 0 .. M + 1) foreach (p; 0 .. 1 << N) foreach (q; 0 .. 1 << N) {
        dp[i][p][q] = INF;
      }
      foreach (p; 0 .. 1 << N) {
        chmin(dp[0][0][p], popcnt(p));
      }
      foreach (i; 0 .. M) {
        foreach (p; 0 .. 1 << N) foreach (q; 0 .. 1 << N) {
          if (dp[i][p][q] >= 0) {
            foreach (s; ps[B[i]]) {
              const r = s ^ p ^ q;
              chmin(dp[i + 1][q][r], dp[i][p][q] + popcnt(r));
            }
          }
        }
      }
      int ans = INF;
      foreach (p; 0 .. 1 << N) {
        chmin(ans, dp[M][p][0]);
      }
      if (ans >= INF) {
        writeln("Impossible");
      } else {
        writeln(ans);
      }
    }
  } catch (EOFException e) {
  }
}