Submission #257623

# Submission time Handle Problem Language Result Execution time Memory
257623 2020-08-04T13:41:05 Z arnold518 Joker (BOI20_joker) C++14
25 / 100
206 ms 262148 KB
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 4e5;
const int SQ = 200;

struct Query
{
	int l, r, k;
	bool operator < (const Query &p) { return r>p.r; }
};

int N, M, Q;
pii E[MAXN+10];
Query A[MAXN+10];
vector<Query> B[MAXN+10];
int ans[MAXN+10];

struct UF
{
	//int par[MAXN+10], sz[MAXN+10], opp[MAXN+10];
	vector<int> par, sz, opp;
	bool state;
	vector<int> V;
	void init()
	{
		par.resize(MAXN+10); sz.resize(MAXN+10); opp.resize(MAXN+10);
		int i, j;
		for(i=1; i<=N; i++) par[i]=i, sz[i]=1, opp[i]=N+i;
		for(i=1; i<=N; i++) par[i+N]=i+N, sz[i+N]=1, opp[i+N]=i;
		V.clear(); state=true;
	}
	int Find(int x)
	{
		if(x==par[x]) return x;
		return par[x]=Find(par[x]);
	}
	void Union(int x, int y)
	{
		//printf("Union %d %d\n", x, y);

		x=Find(x); y=Find(y);
		int nx=opp[x], ny=opp[y];

		if(x==y || !state)
		{
			if(state) V.push_back(-1);
			else V.push_back(-2);
			state=false;
			return;
		}

		if(sz[x]<sz[ny]) swap(x, ny);
		if(sz[y]<sz[nx]) swap(y, nx);
		V.push_back(opp[x]); V.push_back(opp[y]); V.push_back(ny); V.push_back(nx);
		par[ny]=x; sz[x]+=sz[ny];
		par[nx]=y; sz[y]+=sz[nx];
		opp[x]=y; opp[y]=x;
	}
	void restore()
	{
		int ny, nx, x, y, oppx, oppy;
		//printf("RESTORE\n");
		if(V.empty()) while(1);
		if(V.back()<0)
		{
			if(V.back()==-1) state=true;
			V.pop_back();
		 	return;
		}
		nx=V.back(); V.pop_back();
		ny=V.back(); V.pop_back();
		oppy=V.back(); V.pop_back();
		oppx=V.back(); V.pop_back();
		x=par[ny]; y=par[nx];
		opp[x]=oppx; opp[y]=oppy;
		sz[x]-=sz[ny]; sz[y]-=sz[nx];
		par[ny]=ny; par[nx]=nx;
	}
}uf;


int main()
{
	int i, j, k;

	scanf("%d%d%d", &N, &M, &Q);
	for(i=1; i<=M; i++) scanf("%d%d", &E[i].first, &E[i].second);
	for(i=1; i<=Q; i++)
	{
		scanf("%d%d", &A[i].l, &A[i].r);
		A[i].k=i;
		B[A[i].l/SQ].push_back(A[i]);
	}

	uf.init();
	for(i=0, j=1; i<=M/SQ; i++)
	{
		int l=max(SQ*i, 1), r=min(SQ*i+SQ-1, M);
		sort(B[i].begin(), B[i].end());

		for(; j<l; j++) uf.Union(E[j].first, E[j].second);
		int p=M, q;
		for(auto it : B[i])
		{
			for(; p>it.r; p--) uf.Union(E[p].first, E[p].second);
			for(q=l; q<it.l; q++) uf.Union(E[q].first, E[q].second);
			ans[it.k]=uf.state;
			for(q=l; q<it.l; q++) uf.restore();
		}
		for(p++; p<=M; p++) uf.restore();
	}
	for(i=1; i<=Q; i++)
	{
		if(!ans[i]) printf("YES\n");
		else printf("NO\n");
	}
}

Compilation message

Joker.cpp: In member function 'void UF::init()':
Joker.cpp:32:10: warning: unused variable 'j' [-Wunused-variable]
   int i, j;
          ^
Joker.cpp: In function 'int main()':
Joker.cpp:103:23: warning: unused variable 'r' [-Wunused-variable]
   int l=max(SQ*i, 1), r=min(SQ*i+SQ-1, M);
                       ^
Joker.cpp:89:12: warning: unused variable 'k' [-Wunused-variable]
  int i, j, k;
            ^
Joker.cpp:91:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d", &N, &M, &Q);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~
Joker.cpp:92:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(i=1; i<=M; i++) scanf("%d%d", &E[i].first, &E[i].second);
                      ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Joker.cpp:95:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &A[i].l, &A[i].r);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 9 ms 14464 KB Output is correct
2 Correct 11 ms 14464 KB Output is correct
3 Correct 9 ms 14464 KB Output is correct
4 Correct 9 ms 14464 KB Output is correct
5 Correct 9 ms 14464 KB Output is correct
6 Correct 9 ms 14464 KB Output is correct
7 Runtime error 169 ms 262148 KB Execution killed with signal 9 (could be triggered by violating memory limits)
8 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 9 ms 14464 KB Output is correct
2 Correct 11 ms 14464 KB Output is correct
3 Correct 9 ms 14464 KB Output is correct
4 Correct 9 ms 14464 KB Output is correct
5 Correct 9 ms 14464 KB Output is correct
6 Correct 9 ms 14464 KB Output is correct
7 Runtime error 169 ms 262148 KB Execution killed with signal 9 (could be triggered by violating memory limits)
8 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 9 ms 14464 KB Output is correct
2 Correct 11 ms 14464 KB Output is correct
3 Correct 141 ms 26080 KB Output is correct
4 Correct 206 ms 27780 KB Output is correct
5 Correct 159 ms 27616 KB Output is correct
6 Correct 149 ms 26208 KB Output is correct
7 Correct 152 ms 26208 KB Output is correct
8 Correct 159 ms 26268 KB Output is correct
9 Correct 162 ms 26212 KB Output is correct
10 Correct 164 ms 26340 KB Output is correct
11 Correct 162 ms 26212 KB Output is correct
12 Correct 171 ms 26088 KB Output is correct
13 Correct 145 ms 26212 KB Output is correct
14 Correct 152 ms 26080 KB Output is correct
15 Correct 158 ms 26080 KB Output is correct
16 Correct 156 ms 26208 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 9 ms 14464 KB Output is correct
2 Correct 11 ms 14464 KB Output is correct
3 Correct 9 ms 14464 KB Output is correct
4 Correct 9 ms 14464 KB Output is correct
5 Correct 9 ms 14464 KB Output is correct
6 Correct 9 ms 14464 KB Output is correct
7 Runtime error 169 ms 262148 KB Execution killed with signal 9 (could be triggered by violating memory limits)
8 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 9 ms 14464 KB Output is correct
2 Correct 11 ms 14464 KB Output is correct
3 Correct 9 ms 14464 KB Output is correct
4 Correct 9 ms 14464 KB Output is correct
5 Correct 9 ms 14464 KB Output is correct
6 Correct 9 ms 14464 KB Output is correct
7 Runtime error 169 ms 262148 KB Execution killed with signal 9 (could be triggered by violating memory limits)
8 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 9 ms 14464 KB Output is correct
2 Correct 11 ms 14464 KB Output is correct
3 Correct 9 ms 14464 KB Output is correct
4 Correct 9 ms 14464 KB Output is correct
5 Correct 9 ms 14464 KB Output is correct
6 Correct 9 ms 14464 KB Output is correct
7 Runtime error 169 ms 262148 KB Execution killed with signal 9 (could be triggered by violating memory limits)
8 Halted 0 ms 0 KB -