Submission #1043120

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1043120	2024-08-04T00:38:34 Z	wood	Joker (BOI20_joker)	C++17	25 / 100	42 ms	4968 KB

Joker

#include <bits/stdc++.h>
using namespace std;
#define pb push_back

struct dsu{
	vector<bool> side;
	vector<int> rep, size;
	dsu(int n){
		for(int i = 0; i<n; i++){
			rep.pb(i);
			side.pb(0);
			size.pb(1);
		}
	}
	int get(int u){
		if(u == rep[u]) return u;
		int oldparent = rep[u];
		rep[u] = get(rep[u]);
		side[u] = side[u]^side[oldparent];
		return rep[u];
	}
	void merge(int u, int v){
		int oldu = u, oldv = v;
		u = get(u); v = get(v);
		if(size[v]>size[u]){
		       	swap(u,v);
			swap(oldu, oldv);
		 }
		side[v] = !(side[oldv]^side[oldu]);
		size[u]+=size[v];
		rep[v] = u;
	}
};

int main() {
#ifndef ONLINE_JUDGE
	//freopen("/home/ioi/CLionProjects/ioi/input.txt ","r",stdin);
#endif
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int n,m,q; cin>>n>>m>>q;
	vector<pair<int,int>> e;
	for(int i = 0; i<m; i++){
		int a,b; cin>>a>>b;
		a--; b--;
		e.emplace_back(a,b);
	}
	int result[200];
	for(int ii = 0; ii<1; ii++) {
		dsu D(n);
		for(int kk = 0; kk<min(ii,m); kk++) {
			if(D.get(e[kk].first)!=D.get(e[kk].second))
				D.merge(e[kk].first, e[kk].second);
		}
		for(int i = m-1; i>=0; i--) {
			int l = e[i].first, r = e[i].second;
			if(D.get(l)!=D.get(r))
				D.merge(l,r);
			else if(D.side[l]==D.side[r]){
				result[ii] = i;
				break;
			}
		}
	}
	for(int j = 0; j<q; j++){
		int l,b; cin>>l>>b;
		l--;
		if(b>result[l]) cout<<"NO\n";
		else cout<<"YES\n";
	}	
	return 0;
}

Subtask #1
0 / 6.0

#	Verdict	Memory	Grader output
1	Correct	344 KB	Output is correct
2	Correct	348 KB	Output is correct
3	Incorrect	348 KB	Output isn't correct
4	Halted	0 KB	-

Subtask #2
0 / 8.0

#	Verdict	Memory	Grader output
1	Correct	344 KB	Output is correct
2	Correct	348 KB	Output is correct
3	Incorrect	348 KB	Output isn't correct
4	Halted	0 KB	-

Subtask #3
25.0 / 25.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	344 KB	Output is correct
2	Correct	0 ms	348 KB	Output is correct
3	Correct	37 ms	3760 KB	Output is correct
4	Correct	39 ms	4816 KB	Output is correct
5	Correct	39 ms	4820 KB	Output is correct
6	Correct	38 ms	3796 KB	Output is correct
7	Correct	36 ms	3672 KB	Output is correct
8	Correct	38 ms	3540 KB	Output is correct
9	Correct	36 ms	3804 KB	Output is correct
10	Correct	37 ms	4968 KB	Output is correct
11	Correct	38 ms	3756 KB	Output is correct
12	Correct	39 ms	4820 KB	Output is correct
13	Correct	39 ms	2760 KB	Output is correct
14	Correct	42 ms	3364 KB	Output is correct
15	Correct	42 ms	4304 KB	Output is correct
16	Correct	38 ms	4820 KB	Output is correct