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| #include <cstdio> #include <vector> #include <cstring> #include <algorithm> #include <iostream> using namespace std;
typedef long long ll;
typedef pair<int , int > pii; typedef unsigned long long ull;
namespace FastIO { template<typename T> inline T read(T& x) { x = 0; int f = 1; char ch; while (!isdigit(ch = getchar())) if (ch == '-') f = -1; while (isdigit(ch)) x = (x << 1) + (x << 3) + (ch ^ 48), ch = getchar(); x *= f; return x; } template<typename T, typename... Args> inline void read(T& x, Args &...x_) { read(x); read(x_...); return; } inline ll read() { ll x; read(x); return x; } }; using namespace FastIO;
template<int N, int M> class Graph { private : struct Edge { int to, nt; ll wt, fl, cp; Edge() {} Edge(int to, int nt, ll wt, ll cp, ll fl) : to(to), nt(nt), wt(wt), cp(cp), fl(fl) {} }e[M]; int hd[N], cnte; public : inline void clear() { memset(hd, 0, sizeof(hd)), cnte = 0; } inline void AddEdge(int u, int v, ll w = 0, ll c = 0, ll f = 0) { e[++cnte] = Edge(v, hd[u], w, c, f); hd[u] = cnte; } inline int head(int u) { return hd[u]; } inline int nt(int u) { return e[u].nt; } inline int to(int u) { return e[u].to; } inline ll wt(int u) { return e[u].wt; } inline ll& flw(int u) { return e[u].fl; } inline ll& cap(int u) { return e[u].cp; } };
const int MaxV = 1e4 + 10; const int MaxE = 2e4 + 10;
int n, K; Graph< MaxV, MaxE >G;
inline void Input() { read(n, K); if(n == 0 && K == 0) return exit(0); int u, v, w; for(int i = 1; i < n; i++) { read(u, v, w); G.AddEdge(u, v, w); G.AddEdge(v, u, w); } }
ll ans; int vis[MaxV];
namespace Divide { int rt, sz[MaxV], mxs[MaxV];
inline void GetSize(int u, int fa) { sz[u] = 1; for(int i = G.head(u); i; i = G.nt(i)) { int v = G.to(i); if(v == fa || vis[v]) continue; GetSize(v, u); sz[u] += sz[v]; } } inline void GetRoot(int u, int fa, int tot) { mxs[u] = tot - sz[u]; for(int i = G.head(u); i; i = G.nt(i)) { int v = G.to(i); if(v ==fa || vis[v]) continue; GetRoot(v, u, tot); mxs[u] = max(mxs[u], sz[v]); } if(mxs[u] < mxs[rt]) rt = u; }
vector<ll >dis; inline void GetDis(int u, int fa, ll d) { dis.push_back(d); for(int i = G.head(u); i; i = G.nt(i)) { int v = G.to(i); if(v == fa || vis[v]) continue; GetDis(v, u, d + G.wt(i)); } } inline int Calc(int u, ll base) { dis.clear(); GetDis(u, -1, base); sort(dis.begin(), dis.end()); int ans = 0, l = 0, r = dis.size() - 1; while(l < r) { if(dis[l] + dis[r] <= K) { ans += r - l; l++; } else r--; } return ans; }
inline void Init() { GetSize(1, 0); rt = 0; mxs[0] = 1e9; GetRoot(1, 0, sz[1]); } inline void Dfs(int u) { vis[u] = 1; ans += Calc(u, 0); for(int i = G.head(u); i; i = G.nt(i)) { int v = G.to(i); if(vis[v]) continue; ans -= Calc(v, G.wt(i)); GetSize(v, 0); rt = 0, mxs[0] = 1e9; GetRoot(v, 0, sz[v]); Dfs(rt); } } inline void Dfs() { Init(); Dfs(rt); } };
inline void Work() { Divide::Dfs(); printf("%lld\n", ans); }
inline void Clear() { G.clear(); ans = 0; memset(vis, 0, sizeof(vis)); }
int main() { int T = -1; while(T--) { Input(); Work(); Clear(); } return 0; }
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