#include <bits/stdc++.h>
using namespace std;
void read(int &x) {
  int v = 0, f = 1;
  char c = getchar();
  while (!isdigit(c) && c != '-') c = getchar();
  if (c == '-')
    f = -1;
  else
    v = v * 10 + c - '0';
  while (isdigit(c = getchar())) v = v * 10 + c - '0';
  x = v * f;
}
void read(long long &x) {
  long long v = 0ll, f = 1ll;
  char c = getchar();
  while (!isdigit(c) && c != '-') c = getchar();
  if (c == '-')
    f = -1;
  else
    v = v * 10 + c - '0';
  while (isdigit(c = getchar())) v = v * 10 + c - '0';
  x = v * f;
}
void readc(char &x) {
  char c;
  while ((c = getchar()) == ' ')
    ;
  x = c;
}
void writes(string s) { puts(s.c_str()); }
void writeln() { writes(""); }
void writei(int x) {
  if (x < 0) {
    putchar('-');
    x = abs(x);
  }
  if (!x) putchar('0');
  char a[25];
  int top = 0;
  while (x) {
    a[++top] = (x % 10) + '0';
    x /= 10;
  }
  while (top) {
    putchar(a[top]);
    top--;
  }
}
void writell(long long x) {
  if (x < 0) {
    putchar('-');
    x = abs(x);
  }
  if (!x) putchar('0');
  char a[25];
  int top = 0;
  while (x) {
    a[++top] = (x % 10) + '0';
    x /= 10;
  }
  while (top) {
    putchar(a[top]);
    top--;
  }
}
inline long long inc(int &x) { return ++x; }
inline long long inc(long long &x) { return ++x; }
inline long long inc(int &x, long long y) { return x += y; }
inline long long inc(long long &x, long long y) { return x += y; }
inline double inc(double &x, double y) { return x += y; }
inline long long dec(int &x) { return --x; }
inline long long dec(long long &x) { return --x; }
inline long long dec(int &x, long long y) { return x -= y; }
inline long long dec(long long &x, long long y) { return x -= y; }
inline double dec(double &x, double y) { return x -= y; }
inline long long mul(int &x) { return x = ((long long)x) * x; }
inline long long mul(long long &x) { return x = x * x; }
inline long long mul(int &x, long long y) { return x *= y; }
inline long long mul(long long &x, long long y) { return x *= y; }
inline double mul(double &x, double y) { return x *= y; }
inline long long divi(const int &x) {
  long long ans, l, r, mid;
  ans = 0;
  l = 0;
  r = 0x3fffffff;
  while (l < r) {
    mid = (l + r) / 2;
    if (mid * mid <= x) {
      ans = mid;
      l = mid + 1;
    } else
      r = mid;
  }
  return ans;
}
inline long long divi(const long long &x) {
  long long ans, l, r, mid;
  ans = 0;
  l = 0;
  r = 0x3fffffff;
  while (l < r) {
    mid = (l + r) / 2;
    if (mid * mid <= x) {
      ans = mid;
      l = mid + 1;
    } else
      r = mid;
  }
  return ans;
}
inline long long divi(int &x, long long y) { return x /= y; }
inline long long divi(long long &x, long long y) { return x /= y; }
inline double divi(double &x, double y) { return x /= y; }
inline long long mod(int &x, long long y) { return x %= y; }
inline long long mod(long long &x, long long y) { return x %= y; }
int n, m, i, j, k, a[20][20], b[20][20], lx[20], ly[20], ss, visx[20], visy[20],
    dis[20][20], lk[20];
bool dfs(int x) {
  if (visx[x]) return 0;
  visx[x] = 1;
  int i;
  for (i = 0; i < n; i++) {
    if (lx[x] + ly[i] == dis[x][i] && !visy[i]) {
      visy[i] = 1;
      if (lk[i] == -1 || dfs(lk[i])) {
        lk[i] = x;
        return 1;
      }
    }
  }
  return 0;
}
void update() {
  int i, j, add = 0x3bbbbbbb;
  for (i = 0; i < n; i++) {
    if (visx[i]) {
      for (j = 0; j < n; j++) {
        if (!visy[j]) {
          add = min(add, lx[i] + ly[j] - dis[i][j]);
        }
      }
    }
  }
  for (i = 0; i < n; i++) {
    if (visx[i]) lx[i] -= add;
    if (visy[i]) ly[i] += add;
  }
}
int KM() {
  int i, j, k;
  int ans = 0;
  memset(lx, 0, sizeof(lx));
  memset(ly, 0, sizeof(ly));
  memset(lk, -1, sizeof(lk));
  for (i = 0; i < n; i++) {
    for (j = 0; j < n; j++) {
      lx[i] = max(lx[i], dis[i][j]);
    }
    ans += lx[i];
  }
  if (ans <= ss) return 0;
  for (i = 0; i < n; i++) {
    for (;;) {
      memset(visx, 0, sizeof(visx));
      memset(visy, 0, sizeof(visy));
      if (dfs(i)) break;
      update();
      ans = 0;
      for (int i = 0; i < n; i++) {
        ans += lx[i] + ly[i];
      }
      if (ans <= ss) return 0;
    }
  }
  ans = 0;
  for (i = 0; i < n; i++) {
    ans += lx[i] + ly[i];
  }
  return ans;
}
int main() {
  double st = clock();
  cin >> n;
  if ((0) <= (n - 1))
    for ((i) = (0); (i) <= (n - 1); (i)++)
      if ((0) <= (n - 1))
        for ((j) = (0); (j) <= (n - 1); (j)++) cin >> a[i][j];
  if ((0) <= (n - 1))
    for ((i) = (0); (i) <= (n - 1); (i)++)
      if ((0) <= (n - 1))
        for ((j) = (0); (j) <= (n - 1); (j)++) cin >> b[i][j];
  if ((0) <= ((1 << n) - 1))
    for ((i) = (0); (i) <= ((1 << n) - 1); (i)++)
      if (__builtin_popcount(i) == n / 2) {
        if ((0) <= (n - 1))
          for ((j) = (0); (j) <= (n - 1); (j)++) {
            if ((0) <= (n - 1))
              for ((k) = (0); (k) <= (n - 1); (k)++) {
                if ((i >> j) & 1)
                  dis[j][k] = b[j][k];
                else
                  dis[j][k] = a[j][k];
              }
          }
        ss = max(ss, KM());
        if ((clock() - st) / CLOCKS_PER_SEC > 1.5) break;
      }
  cout << ss << endl;
  return 0;
}
