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#include <bits/stdc++.h>
namespace IO {
inline char read() {
static const int IN_LEN = 1000000;
static char buf[IN_LEN], *s, *t;
s == t ? t = (s = buf) + fread(buf, 1, IN_LEN, stdin) : 0;
return s == t ? -1 : *s++;
}
template <typename T>
inline void read(T &x) {
static char c;
static bool iosig;
for (c = read(), iosig = false; !isdigit(c); c = read()) {
if (c == -1) return;
c == '-' ? iosig = true : 0;
}
for (x = 0; isdigit(c); c = read()) x = (x + (x << 2) << 1) + (c ^ '0');
iosig ? x = -x : 0;
}
const int OUT_LEN = 1000000;
char obuf[OUT_LEN], *oh = obuf;
inline void print(char c) {
oh == obuf + OUT_LEN ? (fwrite(obuf, 1, OUT_LEN, stdout), oh = obuf) : 0;
*oh++ = c;
}
template <typename T>
inline void print(T x) {
static int buf[30], cnt;
if (x == 0) {
print('0');
} else {
x < 0 ? (print('-'), x = -x) : 0;
for (cnt = 0; x; x /= 10) buf[++cnt] = x % 10 | 48;
while (cnt) print((char)buf[cnt--]);
}
}
inline void flush() { fwrite(obuf, 1, oh - obuf, stdout); }
}
namespace Task {
#define long long long
int n, mod;
inline void exgcd(long a, long b, long &g, long &x, long &y) {
!b ? (x = 1, y = 0, g = a) : (exgcd(b, a % b, g, y, x), y -= (a / b) * x);
}
inline long getInv(const long x) {
static long tmp1, res, tmp2;
exgcd(x, mod, tmp1, res, tmp2);
return (res % mod + mod) % mod;
}
const int MAXN = 100010;
struct Node {
int v, w;
Node(int v, int w) : v(v), w(w) {}
};
std::vector<Node> edge[MAXN];
inline void addEdge(const int u, const int v, const int w) {
edge[u].push_back(Node(v, w));
edge[v].push_back(Node(u, w));
}
int sz[MAXN], pow[MAXN], inv[MAXN];
bool vis[MAXN];
long ans;
std::map<int, int> cnt;
inline void dfsSize(int u, int fa) {
sz[u] = 1;
for (register int i = 0, v; i < edge[u].size(); i++)
if (!vis[v = edge[u][i].v] && v != fa) dfsSize(v, u), sz[u] += sz[v];
}
inline int getCenter(int u, int fa, int n) {
register int s = n - sz[u];
for (register int i = 0, v; i < edge[u].size(); i++) {
if (!vis[v = edge[u][i].v] && v != fa) {
if (int ret = getCenter(v, u, n)) return ret;
s = std::max(s, sz[v]);
}
}
return (s << 1) <= n ? u : 0;
}
inline void dfs(int u, int fa, int delta, long p, int val) {
cnt[val] += delta;
for (register int i = 0, v; i < edge[u].size(); i++)
if (!vis[v = edge[u][i].v] && v != fa)
dfs(v, u, delta, p * 10 % mod, (val + edge[u][i].w * p) % mod);
}
inline void calc(int u, int fa, int num, long val) {
ans += cnt[(-val * inv[num] % mod + mod) % mod];
for (register int i = 0, v; i < edge[u].size(); i++)
if (!vis[v = edge[u][i].v] && v != fa)
calc(v, u, num + 1, (val * 10 + edge[u][i].w) % mod);
}
inline void solve(int u) {
dfsSize(u, 0), vis[u = getCenter(u, 0, sz[u])] = true, cnt.clear();
for (register int i = 0, v; i < edge[u].size(); i++)
if (!vis[v = edge[u][i].v]) dfs(v, u, 1, 10 % mod, edge[u][i].w);
ans += cnt[0], cnt[0]++;
for (register int i = 0, v; i < edge[u].size(); i++) {
if (!vis[v = edge[u][i].v]) {
dfs(v, u, -1, 10 % mod, edge[u][i].w);
calc(v, u, 1, edge[u][i].w);
dfs(v, u, 1, 10 % mod, edge[u][i].w);
}
}
for (register int i = 0, v; i < edge[u].size(); i++)
if (!vis[v = edge[u][i].v]) solve(v);
}
inline void solve() {
using namespace IO;
read(n), read(mod);
for (register int i = 1, u, v, w; i < n; i++)
read(u), read(v), read(w), addEdge(u + 1, v + 1, w % mod);
pow[0] = inv[0] = 1;
for (int i = 1; i <= n; i++)
pow[i] = (long)pow[i - 1] * 10 % mod, inv[i] = getInv(pow[i]);
solve(1);
print(ans);
}
}
int main() {
#ifdef DBG
freopen("in.in", "r", stdin);
#endif
Task::solve();
IO::flush();
return 0;
}
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