Submission #993861

#	Time	Username	Problem	Language	Result	Execution time	Memory
993861		Fatonim	Joker (BOI20_joker)	C++17	100 / 100	171 ms	17348 KiB

Joker

// "We create our own demons."
#include <bits/stdc++.h>

using namespace std;

#ifdef ONPC
    #include "debug.h"
#else
    #define dbg(...)
#endif

#define int long long
#define ll long long
#define ld long double
#define pi pair<int, int>
// vector
#define sz(a) (int)((a).size())
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define maxel(x) (*max_element(all(x)))
#define minel(x) (*min_element(all(x)))
#define maxpos(x) (max_element(all(x)) - x.begin())
#define minpos(x) (min_element(all(x)) - x.begin())
#define srt(x) (sort(all(x)))
#define rev(x) (reverse(all(x)))
// bitwise operations
#define cnt_bit(n) __builtin_popcountll(n)
#define low_bit(n) ((n) & (-(n)))
#define bit(n, i) (((n) >> (i)) & 1)
#define set_bit(n, i) ((n) | (1LL << (i)))
#define reset_bit(n, i) ((n) & ~(1LL << (i)))
#define flip_bit(n, i) ((n) ^ (1LL << (i)))
// math
#define sqr(n) ((n) * (n))
#define divup(a, b) (((a) + (b)-1) / (b))
// ostream
#define Fixed(a) cout << fixed << setprecision(12) << a;

template <class T> void chmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template <class T> void chmax(T& a, const T& b) { return b > a ? a = b, 1 : 0; }

template <class T> using min_queue = priority_queue<T, vector<T>, greater<T>>;
template <class T> using max_queue = priority_queue<T, vector<T>, less<T>>;

template <class T> using V = vector<T>;
using vi = V<int>;
using vd = V<ld>;
using vb = V<bool>;
using vpi = V<pi>;
using vvi = V<vi>;
using vvb = V<vb>;

const int mod = 1e9 + 7; // 998244353 1e9 + 7
const ll inf = (int)(1e18) + 7;
const int inf_s = 1e9 + 7;
const ld eps = 1e-9;

const int B = 32;
const int N = 1000 + 3;
const int logn = 20;
const int maxn = 2e5 + 7;
/////////////////////////solve/////////////////////////

int n, m, q;
pi e[maxn];
int lst[maxn];

int p[maxn], sz[maxn], len[maxn];
vi hist;

pi get(int a) {
    if (a != p[a]) {
        pi cur = get(p[a]);
        return {cur.first, cur.second ^ len[a]};
    }
    return {a, 0};
}

bool unite(int i) {
    if (i == m) return 0;
    auto [a, x] = get(e[i].first);
    auto [b, y] = get(e[i].second);
    if (a == b) {
        return x ^ y ^ 1;
    }
    if (sz[a] > sz[b]) swap(a, b);
    sz[b] += sz[a];
    p[a] = b;
    len[a] = x ^ y ^ 1;
    hist.push_back(a);
    return 0;
}

void rb(int k) {
    while (sz(hist) > k) {
        int a = hist.back();
        hist.pop_back();
        sz[p[a]] -= sz[a];
        p[a] = a;
        len[a] = 0;
    }
}

void divi(int l, int r, int tl, int tr) {
    if (l > r) return;
    int mid = (l + r) / 2;
    bool ok = 0;
    int k = sz(hist);
    for (int i = l; i < mid; ++i) {
        ok |= unite(i);
    }
    if (ok) {
        lst[mid] = m;
        dbg("d");
    }
    else {
        for (int i = tr; i >= tl; --i) {
            ok |= unite(i);
            if (ok) {
                lst[mid] = i;
                break;
            }
        }
    }
    dbg(l, r, tl, tr, mid, lst[mid]);
    rb(k);
    ok = 0;
    for (int i = l; i <= mid; ++i)
        ok |= unite(i);
    if (ok) {
        for (int i = mid + 1; i <= r; ++i) {
            lst[i] = m;
        }
    }
    else divi(mid + 1, r, lst[mid], tr);
    rb(k);
    ok = 0;
    for (int i = lst[mid] + 1; i <= tr; ++i)
        ok |= unite(i);
    divi(l, mid - 1, tl, lst[mid]);
    rb(k);
}

void solve() {
    cin >> n >> m >> q;

    for (int i = 0; i < n; ++i) {
        sz[i] = 1;
        p[i] = i;
        len[i] = 0;
    }
    
    for (int i = 0; i < m; ++i) {
        int v, u;
        cin >> v >> u;
        --v; --u;

        e[i] = {v, u};
    }

    divi(0, m - 1, 0, m);
    for (int i = 0; i < m; ++i) {
        dbg(lst[i], i);
    }

    while (q--) {
        int l, r;
        cin >> l >> r;
        --l; --r;

        cout << (r < lst[l] ? "YES" : "NO") << "\n";
    }
}

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

#ifdef ONPC
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    freopen("error.txt", "w", stderr);
#endif

    int t = 1;
    //cin >> t;
    for (int i = 1; i <= t; ++i) {
#ifdef ONPC
        cerr << "===========" << i << "===========" << '\n';
#endif
        solve();
    }

#ifdef ONPC
    cerr << endl << "Time " << clock() * 1.0 / CLOCKS_PER_SEC << " sec" << endl;
#endif
}

• Subtask 1: 6 / 6
• Subtask 2: 8 / 8
• Subtask 3: 25 / 25
• Subtask 4: 10 / 10
• Subtask 5: 22 / 22
• Subtask 6: 29 / 29