Submission #931705

#	Time	Username	Problem	Language	Result	Execution time	Memory
931705		sysia	Spring cleaning (CEOI20_cleaning)	C++17	100 / 100	195 ms	29640 KiB

cleaning

//Sylwia Sapkowska
#include <bits/stdc++.h>
#pragma GCC optimize("O3", "unroll-loops")
using namespace std;

void __print(int x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << "'" << x << "'";}
void __print(const char *x) {cerr << '"' << x << '"';}
void __print(const string &x) {cerr << '"' << x << '"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ", "; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? ", " : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifdef LOCAL
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

#define int long long
typedef pair<int, int> T;
const int oo = 1e18, oo2 = 1e9+7, K = 30;
const int mod = 998244353;

struct Tree{
    vector<int>tab, lazy;
    int size = 1;

    Tree(int n){
        while (size < n) size*=2;
        tab.assign(2*size, 0);
        lazy.assign(2*size, 0);
    }

    //xor na przedziale suma na przedziale
    void push(int x, int lx, int rx){
        if (!lazy[x]) return;
        for (auto k: {2*x, 2*x+1}){
            tab[k] = (rx-lx+1)/2 - tab[k];
            lazy[k] ^= 1;
        }
        lazy[x] = 0;
    };

    void update(int x, int lx, int rx, int l, int r){
        if (lx > r || rx < l) return;
        if (lx >= l && rx <= r) {
            tab[x] = rx-lx+1-tab[x];
            lazy[x] ^= 1;
            return;
        }
        int m = (lx+rx)/2;
        push(x, lx, rx);
        update(2*x, lx, m, l, r);
        update(2*x+1, m+1, rx, l, r);
        tab[x] = tab[2*x] + tab[2*x+1];
    }

    int query(int x, int lx, int rx, int l, int r){
        if (lx > r || rx < l) return 0ll;
        if (lx >= l && rx <= r) return tab[x];
        push(x, lx, rx);
        int m = (lx+rx)/2;
        return query(2*x, lx, m, l, r) + query(2*x+1, m+1, rx, l, r);
    }

};

void solve(){
    int n, q; cin >> n >> q;
    vector<vector<int>>g(n+1);
    for (int i = 1; i<n; i++){
        int a, b; cin >> a >> b;
        g[a].emplace_back(b);
        g[b].emplace_back(a);
    }
    vector<int>ord, sz(n+1, 1);
    function<void(int, int)>subsize = [&](int v, int pa){
        for (auto x: g[v]){
            if (x == pa) continue;
            subsize(x, v);
            sz[v] += sz[x];
        }
    };
    subsize(1, 1);
    debug(sz);
    vector<int>pos(n+1), head(n+1), par(n+1);
    function<void(int, int, int)>dfs = [&](int v, int pa, int h){
        pos[v] = (int)ord.size();
        par[v] = pa;
        head[v] = h;
        ord.emplace_back(v);
        int big = -1;
        for (auto x: g[v]){
            if (x == pa) continue;
            if (big == -1 || sz[x] > sz[big]) big = x;
        }
        if (big != -1) dfs(big, v, h);
        for (auto x: g[v]){
            if (x == pa || x == big) continue;
            dfs(x, v, x);
        }
    };
    dfs(1, 0, 1);
    debug(ord);
    debug(head);
    Tree t(n+2);
    vector<bool>leaf(n+1);
    int l = 0;
    auto add = [&](int v){
        while (v){
            int ll = max(1ll, pos[head[v]]);
            if (ll <= pos[v]) {
                t.update(1, 0, t.size-1, ll, pos[v]);
                debug(v, ll, pos[v]);
            }
            v = par[head[v]];
        }
    };
    for (int i = 1; i<=n; i++) {
        leaf[i] = ((int)g[i].size() == 1);
        if (leaf[i]) {
            l++;
            add(i);
        }
    }
    vector<int>ile(n+1);
    auto solve = [&](vector<int>vt){
        int d = (int)vt.size();
        int curr = l;
        auto fix = [&](){
            for (auto x: vt) leaf[x] = ((int)g[x].size() == 1);
            for (auto x: vt){
                if (ile[x]&1) add(x);
                ile[x] = 0;
            }
        };
        for (auto x: vt){
            if (leaf[x]) {
                leaf[x] = 0;
            } else {
                curr++;
                ile[x]++;
                add(x);
            }
        }
        if (curr&1) {
            cout << "-1\n";
            fix();
            return;
        }
        debug(t.query(1, 0, t.size-1, 0, n));
        cout << n-1+d+n-1-t.query(1, 0, t.size-1, 1, n-1) << "\n";
        fix();
    };
    while (q--){
        int d; cin >> d;
        vector<int>vt(d);
        for (auto &x: vt) cin >> x;
        solve(vt);
    }
}

int32_t main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int t = 1;
    //cin >> t;
    while (t--) solve();

    return 0;
}

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