Submission #438666

#	Time	Username	Problem	Language	Result	Execution time	Memory
438666		soroush	Joker (BOI20_joker)	C++17	0 / 100	2087 ms	4556 KiB

Joker

#include <bits/stdc++.h>

using namespace std;

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

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int maxn = 2e5;
const ll mod = 1e9+7;

#define pb push_back
#define endl '\n'
#define dokme(x) cout << x , exit(0)
#define ms(x , y) memset(x , y , sizeof x)
ll pw(ll a, ll b, ll md = mod){ll res = 1;while(b){if(b&1){res=(a*res)%md;}a=(a*a)%md;b>>=1;}return(res);}

int n, m, q;
int a[maxn], b[maxn], l[maxn], r[maxn];

int par[maxn];
bool val[maxn];

int getpar(int v){
	return ((~par[v]) ? par[v] = getpar(par[v]) : v);
}

bool merge(int v, int u){
	int pu = getpar(u) , pv = getpar(v);
	if(pu == pv)
		return val[u] == val[v];
	val[pu] ^= val[v] == val[u];
	par[pv] = pu;
	return 0;
}

bool solve(int l , int r){
	for(int i = 0 ; i < l ; i ++){
		if(merge(a[i], b[i])){
			if(i > n){
				for(int j = 0 ; j < n ; j ++)
					par[j] = -1, val[j] = 0;
			}
			else{
				for(int j = 0; j <= i ; j ++)
					par[a[j]] = par[b[j]] = -1 , val[a[j]] = val[b[j]] = 0;
			}
			return 1;
		}
	}
	for(int i = r ; i < m ; i ++){
		if(merge(a[i], b[i])){
			if(l + i - r > n){
				for(int j = 0 ; j < n ; j ++)
					par[j] = -1, val[j] = 0;
			}
			else{
				for(int j = 0; j < l ; j ++)
					par[a[j]] = par[b[j]] = -1 , val[a[j]] = val[b[j]] = 0;
				for(int j = r ; j <= i ; j ++)
					par[a[j]] = par[b[j]] = -1 , val[a[j]] = val[b[j]] = 0;
			}
			return 1;
		}
	}
	return 0;
}

int32_t main(){
	ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
	cin >> n >> m >> q;
	ms(par, -1);
	for(int i = 0 ; i < m ; i ++)
		cin >> a[i] >> b[i] , a[i] -- , b[i] --;
	for(int i = 0 ; i < q ; i ++)
		cin >> l[i] >> r[i], l[i] --;
	for(int i = 0 ; i < q ; i ++)
		cout << (solve(l[i] , r[i]) ? "YES" : "NO") << endl;
	return(0);
}

• Subtask 1: 0 / 6
• Subtask 2: 0 / 8
• Subtask 3: 0 / 25
• Subtask 4: 0 / 10
• Subtask 5: 0 / 22
• Subtask 6: 0 / 29