oj.uz

Submission #387380

# Submission time Handle Problem Language Result Execution time Memory
387380 2021-04-08T10:13:42 Z kshitij_sodani Tug of War (BOI15_tug) C++14
23 / 100
 67 ms 43116 KB 
//#pragma GCC optimize("Ofast,unroll-loops")
#include <bits/stdc++.h>
using namespace std;
typedef long long llo;
#define mp make_pair
#define pb push_back
#define a first 
#define b second
//#define endl '\n'

int n,k;
int aa[300001];
int bb[300001];
int it[300001];
set<int> pre[300001];
int ans5[300001];
vector<int> adj[300001];
vector<int> adj2[300001];
int vis[300001];
void add(int i,int j){
	adj[2*i+1].pb(2*j);
	adj[2*j+1].pb(2*i);
	/*cout<<2*i+1<<"<<"<<2*j<<endl;
	cout<<2*j+1<<"<<"<<2*i<<endl;
	cout<<endl;*/
}
void add2(int i,int j){
	adj[2*i].pb(2*j+1);
	adj[2*j].pb(2*i+1);
	/*cout<<2*i+1<<"<<"<<2*j<<endl;
	cout<<2*j+1<<"<<"<<2*i<<endl;
	cout<<endl;*/
}
vector<int> ord;
void dfs(int no){
	vis[no]=1;
	pair<int,int> cur2;
	
	cur2.b=(no%2);
	cur2.a=no/2;

	int ind=cur2.a/2;

	if(cur2.b==1){
		if(cur2.a%2==0){
			pre[aa[ind]].erase(cur2.a);
		}
		else{
			pre[bb[ind]].erase(cur2.a);
		}	
	}
	for(auto j:adj[no]){
		if(vis[j]==0){
			dfs(j);
		}
	}
	if(cur2.b==0){
		if(cur2.a%2==0){
			while(pre[aa[ind]].size()){
				int st=0;
				for(auto j:pre[aa[ind]]){
					if(j!=cur2.a){
						//cout<<no<<":"<<j*2+1<<endl;
						dfs(j*2+1);
						st=1;
						break;
					}
				}
				if(st==0){
					break;
				}
			}
		}
		else{
			while(pre[bb[ind]].size()){
				int st=0;
				for(auto j:pre[bb[ind]]){
					if(j!=cur2.a){
					//	cout<<no<<":"<<j*2+1<<endl;
						dfs(j*2+1);
						st=1;
						break;
					}
				}
				if(st==0){
					break;
				}
			}
		}	
	}
	



	ord.pb(no);
}
int cur=0;
void dfs2(int no){
	vis[no]=cur;
	pair<int,int> cur;
	
	cur.b=(no%2);
	cur.a=no/2;

	int ind=cur.a/2;

	if(cur.b==0){
		if(cur.a%2==0){
			pre[aa[ind]].erase(cur.a);
		}
		else{
			pre[bb[ind]].erase(cur.a);
		}	
	}
	for(auto j:adj2[no]){
		if(vis[j]==0){
			dfs2(j);
		}
	}
	if(cur.b==1){
		if(cur.a%2==0){
			while(pre[aa[ind]].size()){
				int st=0;
				for(auto j:pre[aa[ind]]){
					if(j!=cur.a){
						dfs2(j*2);
						st=1;
						break;
					}
				}
				if(st==0){
					break;
				}
			}
		}
		else{
			while(pre[bb[ind]].size()){
				int st=0;
				for(auto j:pre[bb[ind]]){
					if(j!=cur.a){
						dfs2(j*2);
						st=1;
						break;
					}
				}
				if(st==0){
					break;
				}
			}
		}	
	}
}

vector<int> adj3[300001];
int coo[300001];
int kk[300001];
vector<pair<int,int>> pp;
void dfs3(int no){
	kk[no]=1;
	pp.pb({no,it[ans5[no]]});
	for(auto j:adj3[no]){
		if(kk[j]==0){
			dfs3(j);
		}
	}
}
bool dp[2001][2001*2*20];
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cin>>n>>k;
	for(int i=0;i<2*n;i++){
		cin>>aa[i]>>bb[i]>>it[i];
		aa[i]--;
		bb[i]--;
		bb[i]+=n;
		pre[aa[i]].insert(2*i);
		pre[bb[i]].insert(2*i+1);
		add(i*2,i*2+1);
	}
	/*if(n<=10){
		int ans=0;
		for(int i=0;i<(1<<(2*n));i++){
			vector<int> ss;
			vector<int> tt;
			for(int j=0;j<2*n;j++){
				if((1<<j)&i){
					ss.pb(j);
				}
				else{
					tt.pb(j);
				}
			}
			if(ss.size()==n){
				set<int> xx;
				set<int> yy;
				int su=0;
				for(auto j:ss){
					su+=it[j];
					xx.insert(aa[j]);
				}
				for(auto j:tt){
					su-=it[j];
					yy.insert(bb[j]);
				}
				if(abs(su)<=k and xx.size()==n and yy.size()==n){
					ans=1;
				}

			}
		}

		if(ans){
			cout<<"YES"<<endl;
		}
		else{
			cout<<"NO"<<endl;
		}
		return 0;
	}*/

	/*for(int i=0;i<2*n;i++){
		for(auto jj:pre[aa[i]]){
			int j=jj/2;
			if(j!=i){
			//	cout<<i<<":"<<j<<endl;
				//not(j*2) or not(i*2)
			//	add2(i*2,j*2);
			//	continue;
				adj[(j*2)*2].pb(2*(2*i)+1);
				adj[(i*2)*2].pb((j*2)*2+1);
			}
		}
		for(auto jj:pre[bb[i]]){
			int j=jj/2;
			if(j!=i){
			//cout<<i<<","<<j<<endl;
			//	add2(i*2+1,j*2+1);
				//continue;
				adj[(j*2+1)*2].pb(2*(2*i+1)+1);
				adj[(i*2+1)*2].pb((j*2+1)*2+1);
			}
		}
	}
	*/
	for(int i=0;i<8*n;i++){
		for(auto j:adj[i]){
			adj2[j].pb(i);
			//cout<<j<<".."<<i<<endl;
		}
	}


	for(int i=0;i<8*n;i++){
		if(vis[i]==0){
			dfs(i);
		}
	}
	reverse(ord.begin(),ord.end());
	/*for(auto i:ord){
		cout<<i<<":";
	}
	cout<<endl;*/
	for(int i=0;i<2*n;i++){
		pre[aa[i]].insert(i*2);
		pre[bb[i]].insert(i*2+1);
	}
	for(int j=0;j<8*n;j++){
		vis[j]=0;
	}
	for(auto j:ord){
		if(vis[j]==0){
			cur++;
			dfs2(j);
		}
	}
	int st=1;
	for(int i=0;i<8*n;i+=2){
		if(vis[i]==vis[i+1]){
			st=0;
		}

	}

	/*for(int i=0;i<8*n;i++){
		cout<<vis[i]<<",";
	}
	cout<<endl;*/
	if(st){

		for(int i=0;i<8*n;i+=2){
			if(vis[i]<vis[i+1]){
				//i is false
			}
			else{
				//i is true
				if(i%4==0){
					ans5[aa[i/4]]=i/4;
				}
				else{
					ans5[bb[i/4]]=i/4;
				}
			}
		}
		for(int i=0;i<2*n;i++){
			//cout<<ans5[i]<<",";
			if(i<n){
				adj3[i].pb(bb[ans5[i]]);
				coo[adj3[i].back()]++;
			}
			else{
				adj3[i].pb(aa[ans5[i]]);
				coo[adj3[i].back()]++;
			}
		}
		/*cout<<endl;
		for(int i=0;i<2*n;i++){
			cout<<i<<",,"<<adj3[i][0]<<endl;
		}*/

		queue<int> ss;
		for(int i=0;i<2*n;i++){
			if(coo[i]==0){
				ss.push(i);
			}
		}
		while(ss.size()){
			int no=ss.front();
			ss.pop();
			kk[no]=1;
			for(auto j:adj3[no]){
				coo[j]--;
				if(coo[j]==0){
					ss.push(j);
				}
			}

		}
		int su=0;
		int su2=0;
		for(int i=0;i<2*n;i++){
			if(kk[i]==1){
				if(i<n){
					su+=it[ans5[i]];
				}
				else{
					su2+=it[ans5[i]];
				}
			}
			//cout<<kk[i]<<".";
		}
		llo xx5=0;
		for(int i=0;i<2*n;i++){
			xx5+=it[i];
		}
		if(xx5==2*n){
			cout<<"YES"<<endl;
			return 0;
		}
		//cout<<endl;
		//cout<<su<<"<<"<<su2<<endl;
		vector<pair<llo,llo>> con;
		for(int i=0;i<2*n;i++){
			if(kk[i]==0){
				pp.clear();
				dfs3(i);
				llo su3=0;
				llo su4=0;
				llo xx=0;
				for(auto j:pp){
					if(xx==0){
						su3+=j.b;
					}
					else{
						su4+=j.b;
					}
					xx^=1;
					//cout<<j.a<<"?"<<j.b<<endl;
				}
				con.pb({su3,su4});
				//cout<<su3<<"?"<<su4<<endl;
			}
		}
		//cout<<su<<".."<<su2<<endl;
		int zz5=0;
		if(con.size()>30){
			while(true){
				continue;
			}
		}
		dp[0][0]=1;
		for(int i=1;i<=con.size();i++){
			for(int j=con[i-1].a;j<=20*2*n;j++){
				dp[i][j]|=dp[i-1][j-con[i-1].a];
			}
			for(int j=con[i-1].b;j<=20*2*n;j++){
				dp[i][j]|=dp[i-1][j-con[i-1].b];
			}

		}
		llo suu=0;
		for(int i=0;i<2*n;i++){
			suu+=it[i];
		}
		for(int i=0;i<=40*n;i++){
			if(dp[con.size()][i]){
				if(abs(i-(suu-i))<=k){
					zz5=1;
					break;
				}
			}
		}
	/*	for(int i=0;i<(1<<con.size());i++){
			//cout<<i<<endl;
			int dd=su;
			int ee=su2;
			for(int j=0;j<con.size();j++){
				if((1<<j)&i){
					dd+=con[j].a;
					ee+=con[j].b;
				}
				else{
					dd+=con[j].b;
					ee+=con[j].a;
				}
			}
			//cout<<i<<"?"<<dd<<
			if(abs(dd-ee)<=k){

				zz5=1;
				break;
			}
		}*/
		if(zz5==0){
			cout<<"NO"<<endl;
			return 0;
		}


		cout<<"YES"<<endl;
	}
	else{
		cout<<"NO"<<endl;
	}











 
 
	return 0;
}

Compilation message

tug.cpp: In function 'int main()':
tug.cpp:392:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  392 |   for(int i=1;i<=con.size();i++){
      |               ~^~~~~~~~~~~~

Subtask #1
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 35692 KB Output is correct
2 Correct 25 ms 35692 KB Output is correct
3 Correct 25 ms 35692 KB Output is correct
4 Correct 25 ms 35692 KB Output is correct
5 Correct 25 ms 35692 KB Output is correct
6 Correct 26 ms 35692 KB Output is correct
7 Correct 25 ms 35692 KB Output is correct
8 Correct 24 ms 35692 KB Output is correct
9 Correct 25 ms 35692 KB Output is correct
10 Correct 25 ms 35692 KB Output is correct
11 Correct 25 ms 35692 KB Output is correct
12 Correct 25 ms 35692 KB Output is correct
13 Correct 25 ms 35692 KB Output is correct
14 Correct 25 ms 35692 KB Output is correct
15 Correct 24 ms 35820 KB Output is correct
16 Correct 25 ms 35692 KB Output is correct
17 Correct 25 ms 35692 KB Output is correct
18 Correct 26 ms 35692 KB Output is correct
19 Correct 26 ms 35692 KB Output is correct
20 Correct 25 ms 35692 KB Output is correct
21 Correct 26 ms 35564 KB Output is correct
22 Incorrect 25 ms 35692 KB Output isn't correct
23 Halted 0 ms 0 KB -

Subtask #2
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 35692 KB Output is correct
2 Correct 25 ms 35692 KB Output is correct
3 Correct 25 ms 35692 KB Output is correct
4 Correct 25 ms 35692 KB Output is correct
5 Correct 25 ms 35692 KB Output is correct
6 Correct 26 ms 35692 KB Output is correct
7 Correct 25 ms 35692 KB Output is correct
8 Correct 24 ms 35692 KB Output is correct
9 Correct 25 ms 35692 KB Output is correct
10 Correct 25 ms 35692 KB Output is correct
11 Correct 25 ms 35692 KB Output is correct
12 Correct 25 ms 35692 KB Output is correct
13 Correct 25 ms 35692 KB Output is correct
14 Correct 25 ms 35692 KB Output is correct
15 Correct 24 ms 35820 KB Output is correct
16 Correct 25 ms 35692 KB Output is correct
17 Correct 25 ms 35692 KB Output is correct
18 Correct 26 ms 35692 KB Output is correct
19 Correct 26 ms 35692 KB Output is correct
20 Correct 25 ms 35692 KB Output is correct
21 Correct 26 ms 35564 KB Output is correct
22 Incorrect 25 ms 35692 KB Output isn't correct
23 Halted 0 ms 0 KB -

Subtask #3
23.0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 58 ms 41380 KB Output is correct
2 Correct 64 ms 41324 KB Output is correct
3 Correct 63 ms 41324 KB Output is correct
4 Correct 64 ms 41356 KB Output is correct
5 Correct 59 ms 41324 KB Output is correct
6 Correct 66 ms 41324 KB Output is correct
7 Correct 58 ms 41324 KB Output is correct
8 Correct 61 ms 41324 KB Output is correct
9 Correct 57 ms 41324 KB Output is correct
10 Correct 64 ms 41452 KB Output is correct
11 Correct 61 ms 41324 KB Output is correct
12 Correct 64 ms 41324 KB Output is correct
13 Correct 58 ms 41324 KB Output is correct
14 Correct 57 ms 41324 KB Output is correct
15 Correct 64 ms 41324 KB Output is correct
16 Correct 58 ms 41452 KB Output is correct
17 Correct 65 ms 41324 KB Output is correct
18 Correct 58 ms 41324 KB Output is correct
19 Correct 63 ms 41324 KB Output is correct
20 Correct 58 ms 41324 KB Output is correct
21 Correct 67 ms 43116 KB Output is correct
22 Correct 64 ms 41448 KB Output is correct

Subtask #4
0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 35692 KB Output is correct
2 Correct 25 ms 35692 KB Output is correct
3 Correct 25 ms 35692 KB Output is correct
4 Correct 25 ms 35692 KB Output is correct
5 Correct 25 ms 35692 KB Output is correct
6 Correct 26 ms 35692 KB Output is correct
7 Correct 25 ms 35692 KB Output is correct
8 Correct 24 ms 35692 KB Output is correct
9 Correct 25 ms 35692 KB Output is correct
10 Correct 25 ms 35692 KB Output is correct
11 Correct 25 ms 35692 KB Output is correct
12 Correct 25 ms 35692 KB Output is correct
13 Correct 25 ms 35692 KB Output is correct
14 Correct 25 ms 35692 KB Output is correct
15 Correct 24 ms 35820 KB Output is correct
16 Correct 25 ms 35692 KB Output is correct
17 Correct 25 ms 35692 KB Output is correct
18 Correct 26 ms 35692 KB Output is correct
19 Correct 26 ms 35692 KB Output is correct
20 Correct 25 ms 35692 KB Output is correct
21 Correct 26 ms 35564 KB Output is correct
22 Incorrect 25 ms 35692 KB Output isn't correct
23 Halted 0 ms 0 KB -