답안 #127486

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
127486 2019-07-09T12:37:03 Z TadijaSebez Tug of War (BOI15_tug) C++11
23 / 100
75 ms 12408 KB
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
const int N=60050;
vector<pair<int,int>> E[N];
bool was[N];
int n,k;
int sum[2],deg[N];
int sum_dp[N*20],go[N*20],_mx[N*20];
bool dp[N*20];
int main()
{
	int u,v,w;
	scanf("%i %i",&n,&k);
	for(int i=1;i<=2*n;i++)
	{
		scanf("%i %i %i",&u,&v,&w);
		v+=n;
		E[u].pb({v,w});
		E[v].pb({u,w});
		deg[u]++;
		deg[v]++;
	}
	queue<int> q;
	for(int i=1;i<=2*n;i++) if(deg[i]==1) q.push(i),was[i]=1;
	while(q.size())
	{
		int x=q.front();
		q.pop();
		int b=x>n;
		bool ok=0;
		for(auto e:E[x]) if(!was[e.first])
		{
			ok=1;
			v=e.first;
			w=e.second;
		}
		if(!ok || deg[v]==1) return 0*printf("NO\n");
        sum[b]+=w;
        deg[v]--;
		if(deg[v]==1) was[v]=1,q.push(v);
	}
	for(int i=1;i<=2*n;i++) if(!was[i] && deg[i]!=2) return 0*printf("NO\n");
	vector<int> cyc;
	for(int i=1;i<=2*n;i++) if(!was[i])
	{
		int all=0;
		int par=0;
		for(int x=i,t=1,y;;t=-t)
		{
			int w;
			was[x]=1;
			bool ok=0;
			for(auto e:E[x]) if(deg[e.first]==2 && e.first!=par)
			{
				y=e.first;
				w=e.second;
				ok=1;
			}
			if(!ok)
			{
				vector<int> ws;
				for(auto e:E[i]) if(deg[e.first]==2) ws.pb(e.second);
				all=ws[0]-ws[1];
				break;
			}
			all+=t*w;
			par=x;
			x=y;
			if(x==i) break;
		}
		cyc.pb(all);
	}
	/*set<int> dp;
	dp.insert(sum[1]-sum[0]);
	for(int x:cyc)
	{
		vector<int> ins;
		for(int y:dp)
		{
			ins.pb(y+x);
			ins.pb(y-x);
		}
		dp.clear();
		for(int y:ins) dp.insert(y);
	}
	int ans=1e9;
	for(int y:dp) ans=min(ans,abs(y));*/
	/*const int lim=N*10;
	bitset<lim> dp;
	dp[lim/2+sum[1]-sum[0]]=1;
	for(int x:cyc)
	{
		x=abs(x);
		dp=(dp>>x)|(dp<<x);
	}
	int ans=1e9;
	for(int i=0;i<N*20;i++) if(dp[i])
	{
		int x=abs(lim/2-i);
		ans=min(ans,x);
	}*/
	dp[N*10+sum[1]-sum[0]]=1;
	for(int &x:cyc) x=abs(x);
	sort(cyc.begin(),cyc.end());
	for(int i=0,j=0;i<cyc.size();i=j)
	{
		int cnt=0;
		for(j=i;j<cyc.size() && cyc[i]==cyc[j];j++) cnt++;
		if(cyc[i]==0) continue;
		for(int k=0;k<N*20;k++) sum_dp[k]=dp[k]+(k>=cyc[i]*2?sum_dp[k-cyc[i]*2]:0);
		int sz=cyc[i]*2;
		for(int k=0;k<N*20;k++) _mx[k%sz]=k;
		for(int k=0;k<N*20;k++)
		{
			/*if(k<cyc[i]*2) go[k]=k+cyc[i]*cnt;
			else
			{
				go[k]=go[k-cyc[i]*2];
				if(go[k]+cyc[i]*2<N*20) go[k]+=cyc[i]*2;
			}*/
			go[k]=k+cyc[i]*cnt;
			if(go[k]<N*20)
			{
				int tmp=sum_dp[go[k]];//-(k-cyc[i]*cnt>=0?sum_dp[k-cyc[i]*cnt]-dp[k-cyc[i]*cnt]:0);
				if(k-cyc[i]*cnt>=0) tmp-=sum_dp[k-cyc[i]*cnt]-dp[k-cyc[i]*cnt];
				if(tmp>0) dp[k]=1;
				else dp[k]=0;
			}
			else dp[k]=0;
		}
	}
	int ans=1e9+7;
	for(int i=0;i<N*20;i++) if(dp[i]) ans=min(ans,abs(N*10-i));
	//printf("%i\n",ans);
	if(ans<=k) printf("YES\n");
	else printf("NO\n");
	return 0;
}

Compilation message

tug.cpp: In function 'int main()':
tug.cpp:106:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0,j=0;i<cyc.size();i=j)
                  ~^~~~~~~~~~~
tug.cpp:109:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(j=i;j<cyc.size() && cyc[i]==cyc[j];j++) cnt++;
           ~^~~~~~~~~~~
tug.cpp:14:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%i %i",&n,&k);
  ~~~~~^~~~~~~~~~~~~~~
tug.cpp:17:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%i %i %i",&u,&v,&w);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Incorrect 75 ms 12408 KB Output isn't correct
2 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Incorrect 75 ms 12408 KB Output isn't correct
2 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 17 ms 2552 KB Output is correct
2 Correct 14 ms 2552 KB Output is correct
3 Correct 17 ms 2552 KB Output is correct
4 Correct 14 ms 2564 KB Output is correct
5 Correct 16 ms 2552 KB Output is correct
6 Correct 14 ms 2680 KB Output is correct
7 Correct 16 ms 2552 KB Output is correct
8 Correct 14 ms 2552 KB Output is correct
9 Correct 17 ms 2552 KB Output is correct
10 Correct 16 ms 2576 KB Output is correct
11 Correct 16 ms 2552 KB Output is correct
12 Correct 14 ms 2680 KB Output is correct
13 Correct 16 ms 2552 KB Output is correct
14 Correct 16 ms 2564 KB Output is correct
15 Correct 14 ms 2680 KB Output is correct
16 Correct 16 ms 2552 KB Output is correct
17 Correct 14 ms 2652 KB Output is correct
18 Correct 16 ms 2552 KB Output is correct
19 Correct 13 ms 2552 KB Output is correct
20 Correct 16 ms 2552 KB Output is correct
21 Correct 13 ms 2552 KB Output is correct
22 Correct 17 ms 2680 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Incorrect 75 ms 12408 KB Output isn't correct
2 Halted 0 ms 0 KB -