//poj 1741AC代码
#include<iostream>
#include<cstdio>
#include<algorithm>
#include<functional>
#include<cstdlib>
#include<cstring>
#include<vector>
using namespace std;  
const int MAXN = 1e4 + 10;  
  
struct node {  
    int v, w;  
};  
  
int n, k, root, Max, ans;  
vector <node> tree[MAXN];  
vector <int> dis;  
int sz[MAXN], maxv[MAXN];  
bool vis[MAXN];  
  
void init() {  
    memset(vis, false, sizeof(vis));  
    for (int i = 1; i <= n; i++) tree[i].clear();  
}  
  
void dfs_size(int u, int pre) {         // 求出每个子树的大小，以及每个节点的最大儿子  
    sz[u] = 1; maxv[u] = 0;  
    int cnt = tree[u].size();  
    for (int i = 0; i < cnt; i++) {  
        int v = tree[u][i].v;  
        if (v == pre || vis[v]) continue;  
        dfs_size(v, u);  
        sz[u] += sz[v];  
        maxv[u] = max(maxv[u], sz[v]);  
    }  
}  
  
void dfs_root(int r, int u, int pre) {  // 找出以u为根的子树的重心  
    maxv[u] = max(maxv[u], sz[r] - sz[u]);  
    if (Max > maxv[u]) {  
        Max = maxv[u];  
        root = u;  
    }  
    int cnt = tree[u].size();  
    for (int i = 0; i < cnt; i++) {  
        int v = tree[u][i].v;  
        if (v == pre || vis[v]) continue;  
        dfs_root(r, v, u);  
    }  
}  
  
void dfs_dis(int u, int pre, int d) {    // 求出当前子树中所有点到根的距离  
    dis.push_back(d);  
    int cnt = tree[u].size();  
    for (int i = 0; i < cnt; i++) {  
        int v = tree[u][i].v, w = tree[u][i].w;  
        if (v == pre || vis[v]) continue;  
        dfs_dis(v, u, d + w);  
    }  
}  
  
int cal(int u, int d) {         // 计算当前子树中合法的点对数  
    int res = 0;  
    dis.clear(); dfs_dis(u, -1, d);  
    sort (dis.begin(), dis.end());  
    int i = 0, j = dis.size() - 1;  
    while (i < j) {  
        while (dis[i] + dis[j] > k && i < j) --j;  
        res += j - i;  
        ++i;  
    }  
    return res;  
}  
  
void dfs(int u) {               // 总的dfs求解  
    Max = n;  
    dfs_size(u, -1); dfs_root(u, u, -1);  
    ans += cal(root, 0);  
    vis[root] = true;  
    int cnt = tree[root].size(), rt = root; // 一定要注意这样里的root是全局变量，在递归之后可能改变，需要提前保存下来。  
    for (int i = 0; i < cnt; i++) {  
        int v = tree[rt][i].v, w = tree[rt][i].w;  
        if (vis[v]) continue;  
        ans -= cal(v, w);  
        dfs(v);  
    }  
}  
  
int main()
{   
    while (scanf("%d%d", &n, &k), n || k) {  
        init();  
        for (int i = 1; i < n; i++) {  
            int u, v, w;  
            scanf("%d%d%d", &u, &v, &w);  
            tree[u].push_back((node){v, w});  
            tree[v].push_back((node){u, w});  
        }  
        ans = 0;  
        dfs(1);  
        printf("%d\n", ans);  
    }  
    return 0;  
}