Submission #1054518

# Submission time Handle Problem Language Result Execution time Memory
1054518 2024-08-12T10:25:49 Z allin27x Joker (BOI20_joker) C++17
25 / 100
103 ms 12984 KB
#include <bits/stdc++.h>
using namespace std;
const int mod = 1e9+7;
#define forn(i,n) for(int i=0; i<n; i++)
#define readv(a,n) vector<int>a(n);forn(i,n)cin>>a[i];
#define readvv(a,n,m) vector<vector<int>> a(n,vector<int>(m));forn(i,n)forn(j,m)cin>>a[i][j];
#define all(a) a.begin(), a.end()
#define _max(x,y) x = max(x,y)
#define _min(x,y) x = min(x,y)
// #define f first
// #define s second

const int N = 2e5+4;
const int SQRT = 460;
int ans[N];

struct qr{
	int l, r, i;
	bool operator<(qr b){
		return make_pair(l/SQRT, r) < make_pair(b.l/SQRT,b.r);
	}
};

vector<qr> queries[SQRT];
int edges[N][2];

int e1[2*N];
void build1(int N) {for (int i=0; i<N; i++) e1[i] = -1;}
int get1(int x) { return e1[x] < 0 ? x : e1[x] = get1(e1[x]); }
bool conn1(int a, int b) { return get1(a) == get1(b); }
int size1(int x) { return -e1[get1(x)]; }
void unite1(int x, int y) {
	x = get1(x), y = get1(y);
	if (x == y) return;
	if (e1[x] > e1[y]) swap(x, y);
	e1[x] += e1[y];
	e1[y] = x;
}
int nd = 0;
int ch[4*SQRT+6];

int e2[2*N];
void build2(int N) {for (int i=0; i<N; i++) e2[i] = -1;}
int get2(int x) { 
	if (e2[x] < 0) return x;
	ch[nd++] = x;
	return e2[x] = get2(e2[x]); 

}
bool conn2(int a, int b) { return get2(a) == get2(b); }
int size2(int x) { return -e2[get2(x)]; }
void unite2(int x, int y) {
	x = get2(x), y = get2(y);
	if (x == y) return;
	if (e2[x] > e2[y]) swap(x, y);
	e2[x] += e2[y];
	e2[y] = x;
}

int st[2*N];

void solve(){
	int n,m,q; cin>>n>>m>>q;
	for (int i=0; i<m; i++){
		int a,b; cin>>a>>b; a--;b--; edges[i][0]=a; edges[i][1] = b;
	}
	for (int i=0; i<q; i++){
		int l,r; cin>>l>>r; l--; r--;
		qr p; p.l=l;p.r=r;p.i=i;
		queries[l/SQRT].push_back(p);
	}
	for (int i=0; i<SQRT; i++) sort(queries[i].begin(), queries[i].end());
	build1(2*n); build2(2*n);
	int fM =0; 
	for (int t=0; t<SQRT; t++){
		for (int i=0; i<2*n; i++) e2[i] = e1[i],st[i] = e2[i];
		if (t*SQRT >= m) break;
		int fm = 0;
		int i = m-1; int j = queries[t].size()-1;
		while (i>=0){
			if (j<0) break;
			qr p = queries[t][j];
			while (p.r == i){
				int f = 0;
				nd = 0;
				for (int ll=t*SQRT; ll<p.l; ll++){
					if (conn2(edges[ll][0],edges[ll][1])) f++;
					unite2(edges[ll][0]+n, edges[ll][1]);
					unite2(edges[ll][0], edges[ll][1]+n);
				}
				for (int rr =0; rr<nd; rr++){
					e2[ch[rr]] = st[ch[rr]];
				}
				if (f || fm || fM) ans[p.i] = 1;
				j--;
				if (j<0) break;
				p = queries[t][j];
			}
			if (j<0) break;
			nd = 0;
			fm += conn2(edges[i][0], edges[i][1]);
			unite2(edges[i][0] + n, edges[i][1]);
			unite2(edges[i][0], edges[i][1] + n);
			for (int rr =0; rr<nd; rr++){
				st[ch[rr]] = e2[ch[rr]];
			}
			i--;
		}
		for (int ll=SQRT*t; ll<min(m, SQRT*t + SQRT); ll++){
			fM += conn1(edges[ll][0], edges[ll][1]);
			unite1(edges[ll][0] + n, edges[ll][1]);
			unite1(edges[ll][0], edges[ll][1] + n);
		}
	}
	for (int i=0;i<q; i++) cout<<(ans[i]?"YES\n":"NO\n");
}


signed main(){ 
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
	int t=1;
	while(t--){
		solve();
	}	
	return 0;
}

# Verdict Execution time Memory Grader output
1 Correct 1 ms 6488 KB Output is correct
2 Correct 1 ms 6492 KB Output is correct
3 Correct 1 ms 6492 KB Output is correct
4 Correct 1 ms 6492 KB Output is correct
5 Incorrect 1 ms 6492 KB Output isn't correct
6 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 6488 KB Output is correct
2 Correct 1 ms 6492 KB Output is correct
3 Correct 1 ms 6492 KB Output is correct
4 Correct 1 ms 6492 KB Output is correct
5 Incorrect 1 ms 6492 KB Output isn't correct
6 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 6488 KB Output is correct
2 Correct 1 ms 6492 KB Output is correct
3 Correct 78 ms 12984 KB Output is correct
4 Correct 95 ms 10940 KB Output is correct
5 Correct 96 ms 11868 KB Output is correct
6 Correct 83 ms 12156 KB Output is correct
7 Correct 79 ms 11860 KB Output is correct
8 Correct 67 ms 11704 KB Output is correct
9 Correct 79 ms 12028 KB Output is correct
10 Correct 101 ms 11960 KB Output is correct
11 Correct 80 ms 11760 KB Output is correct
12 Correct 98 ms 11740 KB Output is correct
13 Correct 58 ms 11704 KB Output is correct
14 Correct 70 ms 11816 KB Output is correct
15 Correct 91 ms 11704 KB Output is correct
16 Correct 103 ms 11888 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 6488 KB Output is correct
2 Correct 1 ms 6492 KB Output is correct
3 Correct 1 ms 6492 KB Output is correct
4 Correct 1 ms 6492 KB Output is correct
5 Incorrect 1 ms 6492 KB Output isn't correct
6 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 6488 KB Output is correct
2 Correct 1 ms 6492 KB Output is correct
3 Correct 1 ms 6492 KB Output is correct
4 Correct 1 ms 6492 KB Output is correct
5 Incorrect 1 ms 6492 KB Output isn't correct
6 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 6488 KB Output is correct
2 Correct 1 ms 6492 KB Output is correct
3 Correct 1 ms 6492 KB Output is correct
4 Correct 1 ms 6492 KB Output is correct
5 Incorrect 1 ms 6492 KB Output isn't correct
6 Halted 0 ms 0 KB -