func_code_string: #include <bits/stdc++.h>   using namespace std;   using ll = long long;   const int N = 1e2 + 5;   int ans[N][N][N];   bool was[N][N][N];   vector<pair<int, int> > adj[N];   bool calc(int x, int y, int pr) {     if (was[x][y][pr]) return ans[x][y][pr];     was[x][y][pr] = 1;     for (auto to : adj[x]) {       if (to.second >= pr && !calc(y, to.first, to.second)) {         ans[x][y][pr] = 1;         break;       }     }     return ans[x][y][pr];   }   int main() {     ios ::sync_with_stdio(0), cin.tie(0);     int n, m;     cin >> n >> m;     for (int i = 1; i <= m; ++i) {       int u, v;       char c;       cin >> u >> v >> c;       adj[u].push_back({v, c -  a });     }     for (int i = 1; i <= n; ++i) {       for (int j = 1; j <= n; ++j) {         if (!calc(i, j, 0))           cout <<  B ;         else           cout <<  A ;       }       cout <<   n ;     }     return 0;   }   