#include <bits/stdc++.h>
using namespace std;
const int dr[] = {-1, 0, +1, 0};
const int dc[] = {0, +1, 0, -1};
enum {
STAND = 4,
UP = 0,
RIGHT = 1,
DOWN = 2,
LEFT = 3,
NOT_GOOD = 1000000000
};
int n, m, k;
char a[500][500];
int c[500][500];
int f[9][9][500][500];
int g[4][500][500];
vector<pair<int, int>> adj[500][500];
int DP(int z, int i, int j) {
if (g[z][i][j] != -1) return g[z][i][j];
g[z][i][j] = NOT_GOOD;
int zz = (z + c[i][j]) % 4;
int ii = i + dr[zz];
int jj = j + dc[zz];
if (ii < 0 || ii >= n || jj < 0 || jj >= m || a[ii][jj] == 'x') return g[z][i][j] = i * m + j;
return g[z][i][j] = DP(zz, ii, jj);
}
class data_t {
public:
int d, i, j;
data_t(int d, int i, int j) : d(d), i(i), j(j) {}
bool operator<(const data_t& other) const {
return d > other.d;
}
};
int main() {
cin >> k >> m >> n;
for (int i = 0; i < n; i++)
for (int j = 0; j < m; j++) cin >> a[i][j];
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
for (int l = 0; l < k; l++)
for (int r = l; r < k; r++) f[l][r][i][j] = NOT_GOOD;
if (a[i][j] == 'A') {
c[i][j] = +3;
} else if (a[i][j] == 'C') {
c[i][j] = +1;
} else if (a[i][j] == 'x') {
c[i][j] = -1;
} else if (a[i][j] == '.') {
c[i][j] = 0;
} else {
a[i][j] -= '0' + 1;
assert(0 <= a[i][j] && a[i][j] < k);
f[a[i][j]][a[i][j]][i][j] = 0;
}
}
}
memset(g, -1, sizeof g);
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
if (a[i][j] == 'x') continue;
for (int z = 0; z < 4; z++) {
if (DP(z, i, j) == NOT_GOOD) continue;
int ii = DP(z, i, j) / m;
int jj = DP(z, i, j) % m;
adj[i][j].emplace_back(ii, jj);
}
}
}
for (int r = 0; r < k; r++) {
for (int l = r; l >= 0; l--) {
vector<data_t> best;
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
if (a[i][j] == 'x') continue;
for (int mid = l; mid < r; mid++) f[l][r][i][j] = min(f[l][r][i][j], f[l][mid][i][j] + f[mid + 1][r][i][j]);
if (f[l][r][i][j] != NOT_GOOD) best.emplace_back(f[l][r][i][j], i, j);
}
}
sort(best.begin(), best.end());
deque<data_t> q;
while (best.size() || q.size()) {
if (q.empty() || (best.size() && best.back().d <= q.front().d)) q.emplace_front(best.back()), best.pop_back();
data_t cur = q.front();
q.pop_front();
if (f[l][r][cur.i][cur.j] != cur.d) continue;
for (auto [ii, jj] : adj[cur.i][cur.j]) {
if (f[l][r][ii][jj] > cur.d + 1) {
f[l][r][ii][jj] = cur.d + 1;
q.emplace_back(f[l][r][ii][jj], ii, jj);
}
}
}
}
}
int res = NOT_GOOD;
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
if (a[i][j] != 'x') res = min(res, f[0][k - 1][i][j]);
}
}
cout << (res == NOT_GOOD ? -1 : res);
}
