#include <bits/stdc++.h>
using namespace std;
#define int long long
using ii = pair<int, int>;
const int N = 1e5 + 5;
int n, k, sz[N], depth[N], weight[N], pa[N], res;
bool del[N];
vector<int> vertex;
vector<ii> ad[N];
void find_sz(int u, int p){
sz[u] = 1;
for(auto [v, w] : ad[u]) if(v != p && !del[v]){
find_sz(v, u);
sz[u] += sz[v];
}
}
int centroid(int u, int p, int s){
for(auto [v, w] : ad[u])
if(v != p && !del[v] && sz[v] > s/2) return centroid(v, u, s);
return u;
}
struct BIT{
int n;
vector<int> bit;
void init(int s){
bit.clear();
bit.resize(n = s, 0);
}
void update(int i, int y){
for(; i <= n; i += i & -i) bit[i - 1] += y;
}
int get(int i){
int res = 0; i = min(i, n);
for(; i > 0; i -= i & -i) res += bit[i - 1];
return res;
}
} d[N];
int dfs(int u, int p, int root){
pa[u] = root;
vertex.push_back(u);
if(weight[u] >= depth[u]) res += 1;
int mx_depth = depth[u];
for(auto [v, w] : ad[u]) if(v != p && !del[v]){
depth[v] = depth[u] + 1;
weight[v] = max(weight[u], w);
mx_depth = max(mx_depth, dfs(v, u, root));
}
return mx_depth;
}
void solve(int u){
find_sz(u, -1);
u = centroid(u, -1, sz[u]);
del[u] = true;
depth[u] = 0;
vertex.clear();
int mx_depth = 0;
for(auto [v, w] : ad[u]) if(!del[v]){
depth[v] = 1;
weight[v] = w;
int tmp = dfs(v, u, v);
mx_depth = max(mx_depth, tmp);
d[v].init(tmp);
}
d[u].init(mx_depth);
sort(vertex.begin(), vertex.end(), [&](int x, int y){
return weight[x] < weight[y];
});
for(auto x : vertex){
res += d[u].get(weight[x] - depth[x]) - d[pa[x]].get(weight[x] - depth[x]);
d[u].update(depth[x], 1);
d[pa[x]].update(depth[x], 1);
}
for(auto [v, w] : ad[u]) if(!del[v]) solve(v);
}
int32_t main(){
cin.tie(0)->sync_with_stdio(0);
// #define task "test"
// if(fopen(task ".inp", "r")){
// freopen(task ".inp", "r", stdin);
// freopen(task ".out", "w", stdout);
// }
cin >> n >> k;
for(int i = 2; i <= n; i++){
int u, v, w; cin >> u >> v >> w;
ad[u].push_back({v, w - k});
ad[v].push_back({u, w - k});
}
solve(1);
cout << 2 * res << "\n";
return 0;
}
