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#include <iostream>#include <vector>#include <cstring>#include <algorithm>using namespace std;struct edge{int node;int distance;};struct node{vector<edge> adjacent;void destroy(){adjacent.clear();}};int n, k;int ans;int focus;int focus_balance;node tree[10001];vector<int> root2node_k(10001);void init();void divide_and_conquer(int begin, int num);int find_focus(int point, int except, int num);int root2subtree_shell(int root, int subtree, int base, vector<int> <k);int root2subtree(int subtree, int except, int base, vector<int> <k);void self_merge(vector<int> <k, vector<int> §ion);int main(){while(scanf("%d %d", &n, &k), n + k){init();ans = 0;divide_and_conquer(1, n);cout << ans << endl;}return 0;}void init(){int u, v , l;edge temp;for(int i = 1; i <= n; ++i){tree[i].destroy();}for(int i = 1; i <= n - 1; ++i){scanf("%d %d %d", &u, &v, &l);temp.node = v;temp.distance = l;tree[u].adjacent.push_back(temp);temp.node = u;tree[v].adjacent.push_back(temp);}}void divide_and_conquer(int begin, int num){if(tree[begin].adjacent.size()){focus = n;focus_balance = n;find_focus(begin, -1, num);int root = focus;int index = 0;vector<int> deutschland, ltk, section;vector<edge> &ref = tree[root].adjacent;for(int i = 0; i < ref.size(); ++i){index = ltk.size();deutschland.push_back(root2subtree_shell(root, ref[i].node, ref[i].distance, ltk));if(ltk.size() != index){section.push_back(ltk.size() - index);sort(index + ltk.begin(), ltk.end());}}self_merge(ltk, section);for(int i = 0; i < deutschland.size(); ++i){divide_and_conquer(ref[i].node, deutschland[i]);}}}int root2subtree_shell(int root, int subtree, int base, vector<int> <k){int acc = 1;vector<edge> &ref = tree[subtree].adjacent;vector<edge>::iterator buff = ref.begin();if(base <= k){ltk.push_back(base);++ans;}for(int i = 0; i < ref.size(); ++i){if(root == ref[i].node){buff += i;}else{acc += root2subtree(ref[i].node, subtree, base + ref[i].distance, ltk);}}ref.erase(buff);return acc;}int root2subtree(int subtree, int except, int base, vector<int> <k){int acc = 1;vector<edge> &ref = tree[subtree].adjacent;if(base <= k){ltk.push_back(base);++ans;}for(int i = 0; i < ref.size(); ++i){if(ref[i].node != except){acc += root2subtree(ref[i].node, subtree, base + ref[i].distance, ltk);}}return acc;}void self_merge(vector<int> <k, vector<int> §ion){if(section.size() > 1){int l = 0, r;for(int i = 0; i < section.size() - 1; ++i){r = l + section[i];for(int j = i + 1; j < section.size(); ++j){for(int a = l; a < l + section[i]; ++a){int *temp = upper_bound(<k[r], <k[r] + section[j], k - ltk[a]);ans += temp - <k[r];}r += section[j];}l += section[i];}}}int find_focus(int point, int except, int num){int loop = tree[point].adjacent.size();int max = -1;int acc = 1;int temp;for(int i = 0; i < loop; ++i){if(tree[point].adjacent[i].node != except){temp = find_focus(tree[point].adjacent[i].node, point, num);acc += temp;max = max < temp? temp: max;}}max = max < (num - acc)? (num - acc): max;if(max < focus_balance || max == focus_balance && point < focus){focus = point;focus_balance = max;}return acc;}