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#include <iostream>
#include <algorithm>
#include <cstring>
#include <vector>
using namespace std;
const int maxn=200005;
typedef long long ll;
vector<pair<int, int>> graph[10005];
int dp[101][101][28][2];
int rec(int max_pos, int lucas_pos, int last_char, int turn) {
    if(dp[max_pos][lucas_pos][last_char][turn] != -1) {
        return dp[max_pos][lucas_pos][last_char][turn];
    }
    int res;
    if(turn == 0) {
        res = -(2e9);
        for(int i = 0; i < graph[max_pos].size(); i++) {
            int neighbour = graph[max_pos][i].first;
            int next_char = graph[max_pos][i].second;
            
            if(last_char <= next_char) {
                res = max(res, rec(neighbour, lucas_pos, next_char, 1));
            }
        }
    }
    else {
        res = (2e9);
        for(int i = 0; i < graph[lucas_pos].size(); i++) {
            int neighbour = graph[lucas_pos][i].first;
            int next_char = graph[lucas_pos][i].second;
            if(last_char <= next_char) {
                res = min(res, rec(max_pos, neighbour, next_char, 0));
            }
        }
    }
    return dp[max_pos][lucas_pos][last_char][turn] = res;
}
int main()
{
    int n, m;
    cin >> n >> m;
    for(int i = 0; i < m; i++) {
        int a, b;
        char c;
        cin >> a >> b >> c;
        a--; b--;
        graph[a].push_back(make_pair(b, (c - 'a') + 1));
    }
    memset(dp, -1, sizeof dp);
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            if(rec(i, j, 0, 0) == 2e9) {
                cout << "A";
            }
            else {
                cout << "B";
            }
        }
        cout << endl;
    }
    return 0;
}