#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
const int maxn = 1e4 + 15;
int N, lit;
struct Edge
{int to, next, len;Edge() {}Edge(int to, int next, int len): to(to), next(next), len(len) {}
} E[maxn * 2];
int head[maxn], tot;
void initEdge()
{for(int i = 0; i <= N + 5; i++) head[i] = -1;tot = 0;
}
void addEdge(int u, int v, int len)
{E[tot] = Edge(v, head[u], len);head[u] = tot++;E[tot] = Edge(u, head[v], len);head[v] = tot++;
}
int vis[maxn];
int dep[maxn], L, R;
int sz[maxn];
void GetSize(int u, int fa)
{sz[u] = 1;for(int k = head[u]; ~k; k = E[k].next){int v = E[k].to;if(v == fa || vis[v]) continue;GetSize(v, u);sz[u] += sz[v];}
}
void GetRoot(int u, int fa, int tot, int &rt)
{int ma = tot - sz[u];if(ma > tot / 2) return ;for(int k = head[u]; ~k; k = E[k].next){int v = E[k].to;if(v == fa || vis[v]) continue;GetRoot(v, u, tot, rt);ma = max(ma, sz[v]);}if(ma <= tot / 2) rt = u;
}
void GetPath(int u, int fa, int len)
{dep[R++] = len;for(int k = head[u]; ~k; k = E[k].next){int v = E[k].to;if(v == fa || vis[v]) continue;GetPath(v, u, len + E[k].len);}
}
int GetNum(int L, int R)
{int ret = 0;int pos = R - 1;sort(dep + L, dep + R);for(int i = L; i < R; i++){while(pos > i && dep[i] + dep[pos] > lit) pos--;if(pos > i) ret += pos - i;else break;}return ret;
}
int GetAns(int u)
{int ret = 0, rt = 0;GetSize(u, -1);GetRoot(u, -1, sz[u], rt);//找到重心vis[rt] = 1;//重心为分界点for(int k = head[rt]; ~k; k = E[k].next){int v = E[k].to;if(vis[v]) continue;ret += GetAns(v);//不过rt点的个数
    }L = R = 0;for(int k = head[rt]; ~k; k = E[k].next){int v = E[k].to;if(vis[v]) continue;GetPath(v, rt, E[k].len);ret -= GetNum(L, R);L = R;}ret += GetNum(0, R);for(int i = 0; i < R; i++)if(dep[i] <= lit) ret++;else break;vis[rt] = 0;return ret;
}
int main ()
{while(~scanf("%d %d", &N, &lit)){if(N == 0 && lit == 0) break;initEdge();for(int i = 1; i < N; i++){int u, v, len;scanf("%d %d %d", &u, &v, &len);addEdge(u, v, len);}int ans = GetAns(1);printf("%d\n", ans);}return 0;
}