#include <iostream>
#include <cmath>

using namespace std;

const int N = 110;
const double eps = 1e-6;

int n, m;
char g[N][N];
pair<int, int> q[N * N];
int top;

int id = 0;


double get_dist(pair<int, int>& a, pair<int, int>& b) {
    double x = a.first - b.first;
    double y = a.second - b.second;
    return hypot(x, y);
}

double get_hash() {
    double sum = 0;
    for (int i = 0; i < top; ++i) {
        for (int j = i + 1; j < top; ++j) {
            sum += get_dist(q[i], q[j]);
        }
    }
    return sum;
}

char get_id(double key) {
    static double hash[30];
    for (int i = 0; i < id; ++i)
        if (abs(hash[i] - key) < eps)
            return i + 'a';
    hash[id++] = key;
    return id - 1 + 'a';
}

void dfs(int a, int b) {
    q[top++] = {a, b};
    g[a][b] = '0';
    for (int x = a - 1; x <= a + 1; ++x) {
        for (int y = b - 1; y <= b + 1; ++y) {
            if (x == a && y == b) {
                continue;
            }
            if (x >= 0 && x < m && y >= 0 && y < n && g[x][y] == '1') {
                dfs(x, y);
            }
        }
    }
}

int main() {
    cin >> n >> m;

    for (int i = 0; i < m; ++i){
        cin >> g[i];
    }

    for (int i = 0; i < m; ++i) {
        for (int j = 0; j < n; ++j) {
            if (g[i][j] == '1') {
                top = 0;
                dfs(i, j);
                char c = get_id(get_hash());
                for (int k = 0; k < top; ++k) {
                    g[q[k].first][q[k].second] = c;
                }
            }
        }
    }

    for (int i = 0; i < m; ++i) {
        cout << g[i] << endl;
    }

    return 0;
}