package contest200228; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.util.Arrays; import java.util.HashMap; import java.util.InputMismatchException; import java.util.Map; // 21:48 public class E { InputStream is; PrintWriter out; String INPUT = ""; void solve() { int n = ni(), K = ni(); int[] from = new int[n - 1]; int[] to = new int[n - 1]; int[] cs = new int[n-1]; for (int i = 0; i < n - 1; i++) { from[i] = ni() - 1; to[i] = ni() - 1; cs[i] = ni(); } int[][][] g = packWU(n, from, to, cs); int[] cpar = buildCentroidTree(g); dfsTopCT(cpar, g); out.println(ans); } public static int[][][] packWU(int n, int[] from, int[] to, int[] w) { int[][][] g = new int[n][][]; int[] p = new int[n]; for (int f : from) p[f]++; for (int t : to) p[t]++; for (int i = 0; i < n; i++) g[i] = new int[p[i]][2]; for (int i = 0; i < from.length; i++) { --p[from[i]]; g[from[i]][p[from[i]]][0] = to[i]; g[from[i]][p[from[i]]][1] = w[i]; --p[to[i]]; g[to[i]][p[to[i]]][0] = from[i]; g[to[i]][p[to[i]]][1] = w[i]; } return g; } static class Context { boolean[] seps; // is separator? long[] wt; // [ind] = w between sep and ind // long[] dt; int[] vs; int[][] vss; // [neckind][vertices] int[][] ctch; int[][][] g; int[] stack; int[] inds; // int[] neckind; // int[] cpar; } public void dfsTopCT(int[] cpar, int[][][] g) { int n = g.length; int ctroot = -1; for(int i = 0;i < n;i++)if(cpar[i] == -1)ctroot = i; Context cx = new Context(); // cx.cpar = cpar; cx.seps = new boolean[n]; cx.wt = new long[n]; // cx.dt = new long[n]; cx.vs = new int[n]; cx.vss = new int[n][]; cx.ctch = parentToChildren(cpar); cx.g = g; cx.stack = new int[n]; cx.inds = new int[n]; // cx.neckind = new int[n]; dfs(ctroot, cx); } public static int[][] parentToChildren(int[] par) { int n = par.length; int[] ct = new int[n]; for(int i = 0;i < n;i++){ if(par[i] >= 0){ ct[par[i]]++; } } int[][] g = new int[n][]; for(int i = 0;i < n;i++){ g[i] = new int[ct[i]]; } for(int i = 0;i < n;i++){ if(par[i] >= 0){ g[par[i]][--ct[par[i]]] = i; } } return g; } private void dfs(int sep, Context cx) { cx.seps[sep] = true; int neckp = 0; for(int[] neck : cx.g[sep]){ if(cx.seps[neck[0]])continue; int sp = 0; cx.inds[sp] = 0; cx.wt[neck[0]] = neck[1]; // cx.dt[neck[0]] = neck[1]; int vsp = 0; cx.stack[sp++] = neck[0]; while(sp > 0){ int cur = cx.stack[sp-1]; if(cx.inds[sp-1] == 0){ cx.vs[vsp++] = cur; // if(cpar[cur] == sep)cx.neckind[cur] = neckp; } if(cx.inds[sp-1] == cx.g[cur].length){ sp--; continue; } int[] e = cx.g[cur][cx.inds[sp-1]++]; if(!cx.seps[e[0]] && !(sp-2 >= 0 && e[0] == cx.stack[sp-2])){ if((int)(cx.wt[cur]) == e[1] || cx.wt[cur]>>>32 == e[1]) { cx.wt[e[0]] = cx.wt[cur]; }else if(cx.wt[cur] >= 1L<<32) { cx.wt[e[0]] = Long.MAX_VALUE; }else { cx.wt[e[0]] = Math.min(cx.wt[cur], e[1])<<32|Math.max(cx.wt[cur], e[1]); } cx.stack[sp] = e[0]; cx.inds[sp] = 0; sp++; } } cx.vss[neckp] = Arrays.copyOf(cx.vs, vsp); neckp++; } process(sep, cx, Arrays.copyOf(cx.vss, neckp)); for(int e : cx.ctch[sep])dfs(e, cx); } long ans = 0; private void process(int sep, Context cx, int[][] vss) { long[][] wfs = new long[vss.length][]; int p = 0; Map all = new HashMap<>(); long one = 0; Map sides = new HashMap<>(); for(int[] vs : vss) { for(int v : vs) { long w = cx.wt[v]; if(w == Long.MAX_VALUE)continue; ans += match(all, w, one, sides); } for(int v : vs) { long w = cx.wt[v]; if(w == Long.MAX_VALUE)continue; all.put(w, all.getOrDefault(w, 0) + 1); if(w >= 1L<<32) { sides.put(w>>>32, sides.getOrDefault(w>>>32, 0) + 1); sides.put((long)(int)w, sides.getOrDefault((long)(int)w, 0) + 1); }else { one++; } } } for(int val : all.values()) { ans += val; } ans -= one; } long match(Map all, long w, long one, Map sides) { assert w != Long.MAX_VALUE; assert w != 0; long ret = 0; if(w >= 1L<<32) { ret += all.getOrDefault(w, 0); ret += all.getOrDefault(w>>>32, 0); ret += all.getOrDefault((int)w, 0); }else { ret += one; ret -= all.getOrDefault(w, 0); ret += sides.getOrDefault(w, 0); } return ret; } public static int[] buildCentroidTree(int[][][] g) { int n = g.length; int[] ctpar = new int[n]; Arrays.fill(ctpar, -1); buildCentroidTree(g, 0, new boolean[n], new int[n], new int[n], new int[n], ctpar); return ctpar; } private static int buildCentroidTree(int[][][] g, int root, boolean[] sed, int[] par, int[] ord, int[] des, int[] ctpar) { // parent and level-order ord[0] = root; par[root] = -1; int r = 1; for(int p = 0;p < r;p++) { int cur = ord[p]; for(int[] nex : g[cur]){ if(par[cur] != nex[0] && !sed[nex[0]]){ ord[r++] = nex[0]; par[nex[0]] = cur; } } } // if(r == 1)return; // DP and find a separator int sep = -1; // always exists outer: for(int i = r-1;i >= 0;i--){ int cur = ord[i]; des[cur] = 1; for(int[] e : g[cur]){ if(par[cur] != e[0] && !sed[e[0]])des[cur] += des[e[0]]; } if(r-des[cur] <= r/2){ for(int[] e : g[cur]){ if(par[cur] != e[0] && !sed[e[0]] && des[e[0]] >= r/2+1)continue outer; } sep = cur; break; } } sed[sep] = true; for(int[] e : g[sep]){ if(!sed[e[0]])ctpar[buildCentroidTree(g, e[0], sed, par, ord, des, ctpar)] = sep; } return sep; } public static int[][] parents3(int[][] g, int root) { int n = g.length; int[] par = new int[n]; Arrays.fill(par, -1); int[] depth = new int[n]; depth[0] = 0; int[] q = new int[n]; q[0] = root; for (int p = 0, r = 1; p < r; p++) { int cur = q[p]; for (int nex : g[cur]) { if (par[cur] != nex) { q[r++] = nex; par[nex] = cur; depth[nex] = depth[cur] + 1; } } } return new int[][] { par, q, depth }; } static int[][] packU(int n, int[] from, int[] to) { int[][] g = new int[n][]; int[] p = new int[n]; for (int f : from) p[f]++; for (int t : to) p[t]++; for (int i = 0; i < n; i++) g[i] = new int[p[i]]; for (int i = 0; i < from.length; i++) { g[from[i]][--p[from[i]]] = to[i]; g[to[i]][--p[to[i]]] = from[i]; } return g; } void run() throws Exception { is = INPUT.isEmpty() ? System.in : new ByteArrayInputStream(INPUT.getBytes()); out = new PrintWriter(System.out); long s = System.currentTimeMillis(); solve(); out.flush(); if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms"); // Thread t = new Thread(null, null, "~", Runtime.getRuntime().maxMemory()){ // @Override // public void run() { // long s = System.currentTimeMillis(); // solve(); // out.flush(); // if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms"); // } // }; // t.start(); // t.join(); } public static void main(String[] args) throws Exception { new E().run(); } private byte[] inbuf = new byte[1024]; public int lenbuf = 0, ptrbuf = 0; private int readByte() { if(lenbuf == -1)throw new InputMismatchException(); if(ptrbuf >= lenbuf){ ptrbuf = 0; try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); } if(lenbuf <= 0)return -1; } return inbuf[ptrbuf++]; } private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); } private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; } private double nd() { return Double.parseDouble(ns()); } private char nc() { return (char)skip(); } private String ns() { int b = skip(); StringBuilder sb = new StringBuilder(); while(!(isSpaceChar(b))){ // when nextLine, (isSpaceChar(b) && b != ' ') sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } private char[] ns(int n) { char[] buf = new char[n]; int b = skip(), p = 0; while(p < n && !(isSpaceChar(b))){ buf[p++] = (char)b; b = readByte(); } return n == p ? buf : Arrays.copyOf(buf, p); } private int[] na(int n) { int[] a = new int[n]; for(int i = 0;i < n;i++)a[i] = ni(); return a; } private long[] nal(int n) { long[] a = new long[n]; for(int i = 0;i < n;i++)a[i] = nl(); return a; } private char[][] nm(int n, int m) { char[][] map = new char[n][]; for(int i = 0;i < n;i++)map[i] = ns(m); return map; } private int[][] nmi(int n, int m) { int[][] map = new int[n][]; for(int i = 0;i < n;i++)map[i] = na(m); return map; } private int ni() { return (int)nl(); } private long nl() { long num = 0; int b; boolean minus = false; while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')); if(b == '-'){ minus = true; b = readByte(); } while(true){ if(b >= '0' && b <= '9'){ num = num * 10 + (b - '0'); }else{ return minus ? -num : num; } b = readByte(); } } private static void tr(Object... o) { System.out.println(Arrays.deepToString(o)); } }