Submission #380043

#	Time	Username	Problem	Language	Result	Execution time	Memory
380043		Return_0	Joker (BOI20_joker)	C++17	100 / 100	309 ms	12900 KiB

Joker

#pragma GCC optimize("Ofast,unroll-loops")
// #pragma comment(linker, "/stack:200000000")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma,tune=native")

#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;

typedef int ll;
typedef long double ld;
typedef pair <ll, ll> pll;

#ifdef SINA
#define dbg(...) __f(#__VA_ARGS__, __VA_ARGS__)
template <typename Arg1> void __f(const char* name, Arg1&& arg1) { cout << name << " : " << arg1 << std::endl; }
template <typename Arg1, typename... Args> void __f (const char* names, Arg1&& arg1, Args&&... args) {
	const char* comma = strchr(names + 1, ',');cout.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...); }
#define dbg2(x, j, n) cout<< #x << " : "; output((j), (n), x, 1); cout.flush();
#else
#define dbg(...) 0
#define dbg2(x, j, n) 0
#endif
#define SZ(x) ((ll)((x).size()))
#define File(s, t) freopen(s ".txt", "r", stdin); freopen(t ".txt", "w", stdout);
#define input(j, n, a) for (int _i = (j); _i < (n)+(j); _i++) cin>> a[_i];
#define output(j, n, a, t) for (int _i = (j); _i < (n)+(j); _i++) cout<< a[_i] << (((t) && _i != (n)+(j)-1)? ' ' : '\n');
#define kill(x) return cout<< (x) << endl, 0
#define cl const ll
#define fr first
#define sc second
#define lc (v << 1)
#define rc (lc | 1)
#define mid ((l + r) >> 1)
#define All(x) (x).begin(), (x).end()

cl inf = sizeof(ll) == 4 ? (1e9 + 10) : (3e18), mod = 1e9 + 7, MOD = 998244353;

template <class A,class B> ostream& operator << (ostream& out,const pair<A,B>&a){return out<<'('<<a.first<<", "<<a.second<<')';}
template <class A> ostream& operator << (ostream& out, const vector<A> &a) {
	out<< '['; for (int i = -1; ++i < int(a.size());) out<< a[i] << (i + 1 < int(a.size()) ? ", " : ""); return out<<']'; }
template <class T, typename _t = less <T> > using Tree = tree <T, null_type, _t, rb_tree_tag, tree_order_statistics_node_update>;

cl N = 2e5 + 7;

ll e1 [N], e2 [N];

struct DSU {
	ll par [N], sz [N], epr [N], bads;
	bool is [N];
	vector <pll> node;
	inline DSU () { reset(); }
	inline void reset () { iota(par, par + N, 0); fill(sz, sz + N, 1); memset(epr, 0, sizeof epr); node.clear(); memset(is, 0, sizeof is); bads = 0; }

	inline pll root (ll v) {
		ll t = 0;
		for (; v != par[v]; v = par[v]) t ^= epr[v];
		return pll(v, t);
	}

	inline ll unite (ll id) {
		pll x = root(e1[id]), y = root(e2[id]);
		if (x.fr == y.fr) {
			if (x.sc == y.sc) return 0;
			return 1;
		}
		if (sz[x.fr] < sz[y.fr]) swap(x, y);
		is[id] = true;
		node.push_back({y.fr, id});
		sz[x.fr] += sz[y.fr];
		par[y.fr] = x.fr;
		epr[y.fr] = x.sc ^ y.sc ^ 1;
		return 2;
	}

	inline void undo () {
		ll v = node.back().fr;
		sz[par[v]] -= sz[v];
		par[v] = v;
		epr[v] = 0;
		is[node.back().sc] = false;
		node.pop_back();
	}
} ds;

ll dp [N], n, m, q, suff;

void solve (ll l, ll r, ll optl) {
	if (l > r) return;
	ll m = l + r >> 1, opt = m + 1;

	for (ll i = r; i >= m; i--) ds.unite(i);
	solve(l, m - 1, optl);
	if (ds.is[m]) ds.undo();

	for (ll i = optl; i <= m; i++) if (!ds.unite(i)) { opt = i; break; }
	dp[m] = opt;
	for (ll i = opt - 1; i >= optl; i--) if (ds.is[i]) ds.undo();
	for (ll i = m + 1; i <= r; i++) if (ds.is[i]) ds.undo();
	for (ll i = optl; i < opt; i++) ds.unite(i);

	solve(m + 1, r, opt);
	for (ll i = opt - 1; i >= optl; i--) if (ds.is[i]) ds.undo(); // :OBD:
}

int main ()
{
	ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);

	cin>> n >> m >> q;
	for (ll i = 1; i <= m; i++) cin>> e1[i] >> e2[i];

	for (ll i = m; i; i--) if (!ds.unite(i)) { suff = i; break; }

	ds.reset();
	solve(suff, m, 1);

	for (ll l, r; q--;) {
		cin>> l >> r;
		if (r < suff || dp[r] < l) cout<< "YES\n";
		else cout<< "NO\n";
	}

	cerr<< "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";

	return 0;
}
/*

*/

Compilation message (stderr)

Joker.cpp: In function 'void solve(ll, ll, ll)':
Joker.cpp:92:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   92 |  ll m = l + r >> 1, opt = m + 1;
      |         ~~^~~

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