Submission #952864

#	Time	Username	Problem	Language	Result	Execution time	Memory
952864		GrindMachine	Spring cleaning (CEOI20_cleaning)	C++17	34 / 100	1051 ms	44004 KiB

cleaning

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
 
using namespace std;
using namespace __gnu_pbds;
 
template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
 
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl
 
#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)
 
template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}
 
template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}
 
#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif
 
/*
 
 
 
*/
 
const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

vector<ll> adj[N];

struct lca_algo {
    // LCA template (for graphs with 1-based indexing)
 
    int LOG = 1;
    vector<int> depth;
    vector<vector<int>> up;
    vector<int> tin, tout;
    int timer = 1;
 
    lca_algo() {
 
    }
 
    lca_algo(int n, int r) {
        lca_init(n,r);
    }
 
    void lca_init(int n, int r) {
        while ((1 << LOG) < n) LOG++;
        up = vector<vector<int>>(n + 1, vector<int>(LOG, r));
        depth = vector<int>(n + 1);
        tin = vector<int>(n + 1);
        tout = vector<int>(n + 1);
 
        lca_dfs(r, -1);
    }
 
    void lca_dfs(int node, int par) {
        tin[node] = timer++;
 
        trav(child, adj[node]) {
            if (child == par) conts;
 
            up[child][0] = node;
            rep1(j, LOG - 1) {
                up[child][j] = up[up[child][j - 1]][j - 1];
            }
 
            depth[child] = depth[node] + 1;
 
            lca_dfs(child, node);
        }
 
        tout[node] = timer-1;
    }
 
    int lift(int u, int k) {
        rep(j, LOG) {
            if (k & (1 << j)) {
                u = up[u][j];
            }
        }
 
        return u;
    }

    int query(int u, int v) {
        if (depth[u] < depth[v]) swap(u, v);
        int k = depth[u] - depth[v];
        u = lift(u, k);
 
        if (u == v) return u;
 
        rev(j, LOG - 1, 0) {
            if (up[u][j] != up[v][j]) {
                u = up[u][j];
                v = up[v][j];
            }
        }
 
        u = up[u][0];
        return u;
    }
 
    int get_dis(int u, int v) {
        int lca = query(u, v);
        return depth[u] + depth[v] - 2 * depth[lca];
    }
 
    bool is_ances(int u, int v){
        return tin[u] <= tin[v] and tout[u] >= tout[v];
    }
};

vector<ll> depth(N);
vector<ll> leaves(N);
vector<ll> dp(N);
vector<ll> single(N);
vector<bool> leaf(N);
vector<ll> leaf_sum(N);

void dfs1(ll u, ll p){
    leaves[u] = 0;
 
    ll children = 0;
 
    trav(v,adj[u]){
        if(v == p) conts;
        depth[v] = depth[u]+1;
        dfs1(v,u);
        children++;
    }
 
    if(!children){
        leaves[u] = leaf[u] = leaf_sum[u] = single[u] = 1;
        return;
    }
 
    trav(v,adj[u]){
        if(v == p) conts;
        leaves[u] += leaves[v];
    }
    
    leaf_sum[u] = leaves[u];

    if(leaves[u]){
        if(leaves[u]&1){
            dp[u] = depth[u]*(leaves[u]>>1);
            single[u] = (leaves[u] == 1);
            leaves[u] = 1;
        }
        else{
            dp[u] = depth[u]*((leaves[u]-2)>>1);
            leaves[u] = 2;
        }
    }
}

ll parity_sum[N][3][3];

void dfs2(ll u, ll p){
    if(p != -1){
        parity_sum[u][leaves[u]][leaves[p]] = depth[p];
        rep1(j,2){
            rep1(k,2){
                parity_sum[u][j][k] += parity_sum[p][j][k];
            }
        }
    }

    trav(v,adj[u]){
        if(v == p) conts;
        dfs2(v,u);
    }
}

vector<ll> adj2[N];

void solve(int test_case)
{
    ll n,q; cin >> n >> q;
    rep1(i,n-1){
        ll u,v; cin >> u >> v;
        adj[u].pb(v), adj[v].pb(u);
    }
 
    ll root = -1;
    rep1(i,n){
        if(sz(adj[i]) >= 2){
            root = i;
        }
    }

    dfs1(root,-1);
    dfs2(root,-1);
    lca_algo LCA(n,root);

    ll depth_sum = 0;
    rep1(i,n) depth_sum += depth[i]*leaf[i];

    ll leaf_cnt = 0;
    rep1(i,n) leaf_cnt += leaf[i];

    ll sub = 0;
    rep1(i,n) sub += dp[i];

    debug(root);

    while(q--){
        ll k; cin >> k;
        vector<pll> b(k);
        ll curr_depth_sum = depth_sum;
        ll curr_leaf_cnt = leaf_cnt;
        ll curr_sub = sub;
        vector<ll> curr_leaves(n+5);
        rep1(i,n){
            curr_leaves[i] = leaf_sum[i];
        }

        auto is_leaf = leaf;

        rep(i,k){
            ll u; cin >> u;
            b[i] = {LCA.tin[u],u};
            curr_leaf_cnt++;
            curr_depth_sum += depth[u]+1;
            if(is_leaf[u]){
                is_leaf[u] = 0;
                curr_leaves[u] = 0;
                curr_leaf_cnt--;
                curr_depth_sum -= depth[u];
            }
            curr_leaves[u]++;
        }

        sort(all(b));
        rep(i,k-1){
            ll u = b[i].ss, v = b[i+1].ss;
            ll lca = LCA.query(u,v);
            b.pb({LCA.tin[lca],lca});
        }
        b.pb({LCA.tin[root],root});

        sort(all(b));
        b.resize(unique(all(b))-b.begin());
        ll siz = sz(b);
        vector<ll> par(siz);

        stack<ll> stk;
        rep(i,siz){
            ll u = b[i].ss;
            while(!stk.empty() and !LCA.is_ances(stk.top(),u)){
                stk.pop();
            }

            if(i){
                par[i] = stk.top();
                adj2[par[i]].pb(u);
            }

            stk.push(u);
        }

        rev(i,siz-1,0){
            ll u = b[i].ss, p = par[i];
            trav(v,adj2[u]){
                if(curr_leaves[v] != leaves[v]){
                    ll just_below = LCA.lift(v,depth[v]-depth[u]-1);
                    curr_leaves[u] -= leaves[just_below];
                    curr_leaves[u] += 3^leaves[just_below]; 
                }
            }

            curr_sub -= dp[u];

            if(curr_leaves[u]&1){
                curr_sub += depth[u]*(curr_leaves[u]>>1);
                curr_leaves[u] = 1;
            }
            else{
                curr_sub += depth[u]*((curr_leaves[u]-2)>>1);
                curr_leaves[u] = 2;
            }

            if(i and leaves[u] != curr_leaves[u]){
                ll p = par[i];
                ll just_below = LCA.lift(u,depth[u]-depth[p]-1);
                ll sum1 = parity_sum[u][1][2]-parity_sum[just_below][1][2];
                ll sum2 = parity_sum[u][2][1]-parity_sum[just_below][2][1];
                curr_sub += sum1-sum2;
            }

            // ll even_sum = parity_sum[u][0]-parity_sum[p][0];
            // ll odd_sum = parity_sum[u][1]-parity_sum[p][1];
            // ll curr_single_sum = single_sum[u]-single_sum[p];

            // curr_sub += even_sum*ceil2(val[u],2);
            // curr_sub += odd_sum*(val[u]/2);
            // if(val[u] >= 1){
            //     curr_sub -= curr_single_sum;
            // }
        }

        debug(curr_depth_sum);

        ll ans = curr_depth_sum-curr_sub*2;
        if(curr_leaf_cnt&1) ans = -1;
        cout << ans << endl;

        for(auto [ti,u] : b){
            // val[u] = -leaf[u];
            adj2[u].clear();
        }
    }
}
 
int main()
{
    fastio;
 
    int t = 1;
    // cin >> t;
 
    rep1(i, t) {
        solve(i);
    }
 
    return 0;
}

Compilation message (stderr)

cleaning.cpp: In function 'void dfs1(ll, ll)':
cleaning.cpp:166:43: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
  166 |         leaves[u] = leaf[u] = leaf_sum[u] = single[u] = 1;
cleaning.cpp: In function 'void solve(int)':
cleaning.cpp:46:18: warning: statement has no effect [-Wunused-value]
   46 | #define debug(x) 42
      |                  ^~
cleaning.cpp:238:5: note: in expansion of macro 'debug'
  238 |     debug(root);
      |     ^~~~~
cleaning.cpp:296:29: warning: unused variable 'p' [-Wunused-variable]
  296 |             ll u = b[i].ss, p = par[i];
      |                             ^
cleaning.cpp:46:18: warning: statement has no effect [-Wunused-value]
   46 | #define debug(x) 42
      |                  ^~
cleaning.cpp:335:9: note: in expansion of macro 'debug'
  335 |         debug(curr_depth_sum);
      |         ^~~~~

• Subtask 1: 0 / 0
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 16 / 16
• Subtask 5: 0 / 19
• Subtask 6: 0 / 17
• Subtask 7: 0 / 30