func_code_string: #include <bits/stdc++.h>   using namespace std;   template <typename T>   void mnm(T &a, T b) {     a = min(a, b);   };   template <typename T>   void mxm(T &a, T b) {     a = max(a, b);   };   template <typename T>   int discrete_id(vector<T> &vals, T val, int startId = 1) {     return startId +            (int)(lower_bound(vals.begin(), vals.end(), val) - vals.begin());   }   long long power(long long a, long long n, long long mod) {     long long ans = 1;     while (n) {       if (n & 1) ans = (ans * a) % mod;       a = (a * a) % mod;       n /= 2;     }     return ans;   }   long long modul(long long x, long long mod) {     x %= mod;     if (x < 0) x += mod;     return x;   }   tuple<long long, long long, long long> eea(long long x, long long y) {     if (y == 0) return {1LL, 0LL, x};     long long a, b, d, q = x / y;     tie(a, b, d) = eea(y, x % y);     return {b, a - b * q, d};   }   long long inv(long long x, long long m) {     long long a, b, d;     tie(a, b, d) = eea(x, m);     assert(d == 1);     return modul(a, m);   }   char i2c(int c) { return (char)(c +  0 ); }   int get_subtree_sz(int u, int pa, vector<vector<pair<int, int>>> &adj,                      vector<bool> &deleted, vector<int> &subsz) {     subsz[u] = 1;     for (auto e : adj[u]) {       int v = e.first;       if (v != pa && !deleted[v]) {         subsz[u] += get_subtree_sz(v, u, adj, deleted, subsz);       }     }     return subsz[u];   }   int get_centroid(int u, int pa, int desired,                    vector<vector<pair<int, int>>> &adj, vector<bool> &deleted,                    vector<int> &subsz) {     for (auto e : adj[u]) {       int v = e.first;       if (v != pa && !deleted[v] && subsz[v] > desired) {         return get_centroid(v, u, desired, adj, deleted, subsz);       }     }     return u;   }   int neg(int u, int mod) { return (mod - u) % mod; }   void visit(int u, int pa, vector<vector<pair<int, int>>> &adj,              vector<bool> &deleted, map<int, int> &need_up, map<int, int> &cnt_up,              long long &ans, bool add, int _10pd, int _10pmd, int inv10,              int cur_up, int cur_down, int m, int depth = 1) {     if (add) {       ans += cnt_up[(1LL * neg(cur_down, m) * _10pmd) % m];       ans += need_up[cur_up];     } else {       ++cnt_up[cur_up];       ++need_up[(1LL * neg(cur_down, m) * _10pmd) % m];     }     for (auto e : adj[u]) {       int v, w;       tie(v, w) = e;       if (v != pa && !deleted[v]) {         w %= m;         int new_down = (10LL * cur_down + w) % m;         int new_up = (1LL * w * _10pd + cur_up) % m;         visit(v, u, adj, deleted, need_up, cnt_up, ans, add, (10LL * _10pd) % m,               (1LL * inv10 * _10pmd) % m, inv10, new_up, new_down, m, depth + 1);       }     }   }   long long centroid_decomp(int u, vector<vector<pair<int, int>>> &adj,                             vector<bool> &deleted, vector<int> &subsz,                             map<int, int> &need_up, map<int, int> &cnt_up, int m,                             int inv10) {     u = get_centroid(u, 0, get_subtree_sz(u, 0, adj, deleted, subsz) / 2, adj,                      deleted, subsz);     deleted[u] = true;     cnt_up[0] = 1;     need_up[0] = 1;     long long ans = 0;     for (auto e : adj[u]) {       int v, w;       tie(v, w) = e;       if (!deleted[v]) {         w %= m;         visit(v, u, adj, deleted, need_up, cnt_up, ans, true, 10 % m, inv10,               inv10, w, w, m);         visit(v, u, adj, deleted, need_up, cnt_up, ans, false, 10 % m, inv10,               inv10, w, w, m);       }     }     cnt_up.clear();     need_up.clear();     for (auto e : adj[u]) {       int v = e.first;       if (!deleted[v]) {         long long tmp =             centroid_decomp(v, adj, deleted, subsz, need_up, cnt_up, m, inv10);         ans += tmp;       }     }     return ans;   }   int main() {     ios::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int n, m;     cin >> n >> m;     vector<vector<pair<int, int>>> adj(n + 1);     for (int i = (int)(1); i <= (int)(n - 1); ++i) {       int u, v, w;       cin >> u >> v >> w;       adj[u].emplace_back(v, w);       adj[v].emplace_back(u, w);     }     vector<bool> deleted(n + 1, 0);     vector<int> subsz(n + 1);     map<int, int> need_up, cnt_up;     long long a, b, d;     tie(a, b, d) = eea(10LL, m);     int inv10 = modul(a, m);     cout << centroid_decomp(0, adj, deleted, subsz, need_up, cnt_up, m, inv10)          <<   n ;   }   