func_code_string: #include <bits/stdc++.h>   using namespace std;   void solve();   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     solve();     return 0;   }   const int inf = 2e9;   const long long linf = 2e18;   const long long mod = 998244353;   const int N = 2e5 + 100;   vector<int> g[N];   struct Elem {     int value, node, pos;   };   Elem merge(Elem a, Elem b) {     if (a.value < b.value)       return b;     else       return a;   }   struct T {     vector<Elem> t;     vector<int> u;     T(const vector<Elem> &a) {       t.assign(4 * a.size(), {0, 0});       u.assign(4 * a.size(), 0);       build(a, 0, 0, a.size());     }     void build(const vector<Elem> &a, int v, int l, int r) {       if (r - l == 1) {         t[v] = a[l];         return;       }       build(a, v * 2 + 1, l, (l + r) >> 1);       build(a, v * 2 + 2, (l + r) >> 1, r);       t[v] = merge(t[v * 2 + 1], t[v * 2 + 2]);     }     void push(int v, int l, int r) {       if (r - l == 1) {         t[v].value += u[v];         u[v] = 0;         return;       }       t[v].value += u[v];       u[v * 2 + 1] += u[v];       u[v * 2 + 2] += u[v];       u[v] = 0;     }     Elem get(int v, int l, int r, int vl, int vr) {       push(v, l, r);       if (vl >= r || vr <= l) return {-inf, -1};       if (vl <= l && r <= vr) return t[v];       if (r - l == 1) {         return t[v];       }       return merge(get(v * 2 + 1, l, (l + r) >> 1, vl, vr),                    get((v * 2 + 2), (l + r) >> 1, r, vl, vr));     }     void upd(int v, int l, int r, int vl, int vr, int d) {       push(v, l, r);       if (vl >= r || vr <= l) return;       if (vl <= l && r <= vr) {         u[v] += d;         push(v, l, r);         return;       }       int m = (l + r) >> 1;       upd(v * 2 + 1, l, m, vl, vr, d);       upd(v * 2 + 2, m, r, vl, vr, d);       t[v] = merge(t[v * 2 + 1], t[v * 2 + 2]);     }   };   vector<Elem> leaves;   pair<int, int> segments[N];   int par[N];   pair<int, int> dfs(int v, int depth = 1) {     if (g[v].size() == 1 && par[v] != -1) {       int pos = leaves.size();       leaves.push_back({depth, v, pos});       return {leaves.size() - 1, leaves.size() - 1};     }     for (auto u : g[v]) {       if (par[v] == u) continue;       par[u] = v;       auto [l, r] = dfs(u, depth + 1);       segments[v].first = min(segments[v].first, l);       segments[v].second = max(segments[v].second, r);     }     return segments[v];   }   int marked[N];   void solve() {     int n, k;     cin >> n >> k;     fill(par, par + n, -1);     for (int i = 0; i < n; i++) segments[i] = {inf, -inf};     for (int i = 0; i < n - 1; i++) {       int t1, t2;       cin >> t1 >> t2;       t1--;       t2--;       g[t1].push_back(t2);       g[t2].push_back(t1);     }     dfs(0);     T t(leaves);     int unmarked = n;     long long best = -1ll * (n / 2) * (n - n / 2);     for (int i = 1; i <= k; i++) {       if (i > leaves.size()) {         long long rmax = max((long long)leaves.size(), (long long)min(i, n / 2));         best = max(best, rmax * (n - rmax));         continue;       }       Elem e = t.get(0, 0, leaves.size(), 0, leaves.size());       t.upd(0, 0, leaves.size(), e.pos, e.pos + 1, -inf);       int v = e.node;       marked[v] = true;       unmarked--;       v = par[v];       while (!marked[v]) {         marked[v] = true;         unmarked--;         t.upd(0, 0, leaves.size(), segments[v].first, segments[v].second + 1, -1);         if (par[v] == -1) break;         v = par[v];       }       long long bmax = min(n / 2, unmarked);       best = max(best, 1ll * i * (n - i) - bmax * (n - bmax));     }     cout << best <<   n ;   }   