Submission #898757

#	Time	Username	Problem	Language	Result	Execution time	Memory
898757		gaga999	Joker (BOI20_joker)	C++17	100 / 100	1673 ms	15184 KiB

Joker

#include <cstdio>
#include <stdio.h>
#include <iostream>
#include <math.h>
#include <vector>
#include <queue>
#include <stack>
#include <deque>
#include <algorithm>
#include <utility>
#include <set>
#include <map>
#include <stdlib.h>
#include <cstring>
#include <string.h>
#include <string>
#include <sstream>
#include <assert.h>
#include <climits>
#include <sstream>
#include <numeric>
#include <time.h>
#include <limits.h>
#include <list>
#include <bitset>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <iomanip>
#include <complex>
#include <chrono>
#include <fstream>
#include <functional>
#include <unistd.h>
// #pragma GCC optimize("Ofast,no-stack-protector")
// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx,avx2,bmi,bmi2,lzcnt,popcnt")
#define lowbit(x) ((x) & -(x))
#define ml(a, b) ((1ll * (a) * (b)) % M)
#define tml(a, b) (a) = ((1ll * (a) * (b)) % M)
#define ad(a, b) ((0ll + (a) + (b)) % M)
#define tad(a, b) (a) = ((0ll + (a) + (b)) % M)
#define mi(a, b) ((0ll + M + (a) - (b)) % M)
#define tmi(a, b) (a) = ((0ll + M + (a) - (b)) % M)
#define tmin(a, b) (a) = min((a), (b))
#define tmax(a, b) (a) = max((a), (b))
#define iter(a) (a).begin(), (a).end()
#define riter(a) (a).rbegin(), (a).rend()
#define init(a, b) memset((a), (b), sizeof(a))
#define cpy(a, b) memcpy((a), (b), sizeof(a))
#define uni(a) a.resize(unique(iter(a)) - a.begin())
#define pb emplace_back
#define mpr make_pair
#define ls(i) ((i) << 1)
#define rs(i) ((i) << 1 | 1)
#define INF 0x3f3f3f3f
#define NIF 0xc0c0c0c0
#define eps 1e-9
#define F first
#define S second
#define AC cin.tie(0)->sync_with_stdio(0)
using namespace std;
typedef long long llt;
typedef pair<int, int> pii;
typedef pair<double, double> pdd;
typedef pair<llt, llt> pll;
typedef complex<double> cd;
// const int M = 998244353;

// random_device rm;
// mt19937 rg(rm());
// default_random_engine rg(rm());
// uniform_int_distribution<int> rd(INT_MIN, INT_MAX);
// uniform_real_distribution<double> rd(0, M_PI);

void db() { cerr << "\n"; }
template <class T, class... U>
void db(T a, U... b) { cerr << a << " ", db(b...); }

inline char gc()
{
    const static int SZ = 1 << 16;
    static char buf[SZ], *p1, *p2;
    if (p1 == p2 && (p2 = buf + fread(p1 = buf, 1, SZ, stdin), p1 == p2))
        return -1;
    return *p1++;
}
void rd() {}
template <typename T, typename... U>
void rd(T &x, U &...y)
{
    x = 0;
    bool f = 0;
    char c = gc();
    while (!isdigit(c))
        f ^= !(c ^ 45), c = gc();
    while (isdigit(c))
        x = (x << 1) + (x << 3) + (c ^ 48), c = gc();
    f && (x = -x), rd(y...);
}

template <typename T>
void prt(T x)
{
    if (x < 0)
        putchar('-'), x = -x;
    if (x > 9)
        prt(x / 10);
    putchar((x % 10) ^ 48);
}

const int N = 2e5 + 5, B = 450;
int u[N], v[N], l[N], r[N], ds[N << 1], ln = -1, n;
bool an[N];
pii rm[N << 1];
vector<int> qs[N];

int f(int x)
{
    return ds[x] < 0 ? x : f(ds[x]);
}

inline void mg(int i, int j)
{
    i = f(i), j = f(j);
    if (i != j)
    {
        if (ds[i] > ds[j])
            swap(i, j);
        rm[++ln] = mpr(j, ds[j]);
        ds[i] += ds[j], ds[j] = i;
    }
}

inline void undo(int p)
{
    while (ln > p)
        ds[ds[rm[ln].F]] -= rm[ln].S, ds[rm[ln].F] = rm[ln].S, ln--;
}

inline void add(int i)
{
    mg(u[i], v[i] + n), mg(v[i], u[i] + n);
}

signed main()
{
    int m, q;
    rd(n, m, q);
    for (int i = 1; i <= m; i++)
        rd(u[i], v[i]);
    for (int i = 0; i < q; i++)
    {
        rd(l[i], r[i]);
        qs[(l[i] - 1) / B].pb(i);
    }
    init(ds, -1);
    for (int t = 0, cl = 0; cl <= m; t++, cl += B)
    {
        if (qs[t].empty())
            continue;
        sort(iter(qs[t]), [&](int a, int b)
             { return r[a] > r[b]; });
        bool ok = 0;
        for (int i = 1; i <= cl; i++)
        {
            if (ok)
                break;
            if (f(u[i]) == f(v[i]))
                ok = 1;
            else
                add(i);
        }
        int cr = m;
        for (int i : qs[t])
        {
            if (ok)
                an[i] = 1;
            else
            {
                while (cr > r[i])
                {
                    if (f(u[cr]) == f(v[cr]))
                        ok = 1;
                    else
                        add(cr--);
                    if (ok)
                        break;
                }
                if (ok)
                    an[i] = 1;
                else
                {
                    int pl = ln;
                    for (int j = max(1, cl); j < l[i]; j++)
                    {
                        if (f(v[j]) == f(u[j]))
                        {
                            an[i] = 1;
                            break;
                        }
                        add(j);
                    }
                    undo(pl);
                }
            }
        }
        init(ds, -1), ln = -1;
    }
    for (int i = 0; i < q; i++)
        puts(an[i] ? "YES" : "NO");
}

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