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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#104509#6329. Colorful GraphyangjlTL 2ms9552kbC++204.8kb2023-05-10 21:43:262023-05-10 21:43:28

Judging History

你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2023-05-10 21:43:28]
  • 评测
  • 测评结果:TL
  • 用时:2ms
  • 内存:9552kb
  • [2023-05-10 21:43:26]
  • 提交

answer

#include<iostream>
#include<cmath>
#include<cstring>
#include<cassert>
#include<string>
#include<queue>
#include<deque>
#include<stack>
#include<algorithm>
#include<unordered_map>
#include<map>
#include<vector>
#include<set>
#include<unordered_set>
#include<bitset>
#include<climits>
#include<numeric>
#include<functional>
#include<iomanip>
#include<random>
#ifdef YJL
#include<debug.h>
#else
#define debug(args...)0
#define debug_n(a,n)0
#endif
using namespace std;
typedef long long ll;

const int N = 2e5 + 10;
int n,m;
namespace Tarjan {
    struct ty {
        int t,l,next;
    } edge[int(2e6)+10];
    int en,head[N];
    void initGraph(int n) {
        fill_n(head+1,n,-1),en=0;
    }
    void addEdge(int x,int y,int z=0) {
        edge[en]={y,z,head[x]};
        head[x]=en++;
    }
    int dfn[N], low[N], dn;
    int sta[N], insta[N], top;
    int color[N], cn;
    void tarjan(int u) {
        dfn[u]=low[u]=++dn;
        sta[++top]=u;
        insta[u]=1;
        for (int i=head[u]; ~i; i=edge[i].next) {
            int v=edge[i].t;
            if (!dfn[v]) {
                tarjan(v);
                low[u]=min(low[u], low[v]);
            } else if (insta[v])// 返祖边和横插边
                low[u]=min(low[u], dfn[v]);
        }
        if (dfn[u]==low[u]) {
            ++cn;
            for (int v=-1; v!=u;) {
                v=sta[top--];
                insta[v]=0;
                color[v]=cn;
            }
        }
    }
    void converge(int n) {
        fill_n(dfn+1,n,0), dn=cn=0;
        for(int i=1; i<=n; ++i)
            if(!dfn[i])
                tarjan(i);
    }
    auto newGraph() {
        vector<pair<int,int>> e;
        for(int u=1; u<=n; ++u) {
            for(int _i=head[u]; ~_i; _i=edge[_i].next) {
                int v=edge[_i].t;
                if(color[u]!=color[v])
                    e.emplace_back(color[u],color[v]);
            }
        }
        return e;
    }
}
namespace NetFlow {
    using T=int;
	const T INF=T(1)<<(sizeof(T)*8-2);
    const int _V=10000+10;
    const int _E=200000*2+10;
	int s0=_V-1,t0=s0-1;
    int head[_V],en;
	struct ty {
		int t, next;
        T l;
	} edge[_E];
    void initGraph() {
		memset(head, -1, sizeof(head)), en=0;
	}
	void addEdge(int x, int y, T z=0) {
		edge[en]= {y, head[x], z};
        head[x]=en++;
		if(en&1) addEdge(y, x);
	}
    int dis[_V];
	bool bfs(int s,int t) {
        memset(dis,-1,sizeof dis);
	    queue<int> q;
        dis[s]=0;
		q.push(s);
		while(q.size()) {
			int u=q.front();
			q.pop();
			for (int i=head[u]; ~i; i=edge[i].next) {
				int v=edge[i].t;
				if(dis[v]==-1&&edge[i].l>0) {
					dis[v]=dis[u]+1;
					q.push(v);
				}
			}
		}
		return dis[t]!=-1;
	}
	T dfs(int u, T flow,int t) {
		if(u==t) return flow;
		T ans=flow;
		for (int i=head[u]; ~i&&ans; i=edge[i].next) {
			int v=edge[i].t;
			if (dis[v]==dis[u]+1&&edge[i].l>0) {
				T tmp=dfs(v, min(edge[i].l, ans), t);
				edge[i].l-=tmp;
				edge[i^1].l+=tmp;
				ans-=tmp;
			}
		}
		if(ans==flow) dis[u]=-1;
		return flow-ans;
	}
	T dinic(int s,int t) {
		T ans=0;
		while(bfs(s,t)) ans+=dfs(s,INF,t);
		return ans;
	}
    int find_next(int u) {
        for(int _i=head[u]; ~_i; _i=edge[_i].next) {
            int v=edge[_i].t;
            if(_i%2==0 && edge[_i^1].l && v!=s0 && v!=t0) {
                edge[_i].l++;
                edge[_i^1].l--;
                return v;
            }
        }
        return -1;
    }
}
using namespace NetFlow;

int main() {
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    cin>>n>>m;
    Tarjan::initGraph(n);
    while(m--) {
        int u,v;
        cin>>u>>v;
        Tarjan::addEdge(u,v);
    }
    Tarjan::converge(n);
    auto edg=Tarjan::newGraph();
    debug_n(Tarjan::color+1,n);
    debug(edg);
 
    int nn=Tarjan::cn;
    initGraph();
    for(int i=1; i<=nn; ++i) {
        addEdge(s0,i,1);
        addEdge(i+nn,t0,1);
    }
    for(auto [u,v]:edg) {
        addEdge(u,v+nn,INF);
        addEdge(u,v,INF);
    }
    int flow=dinic(s0,t0);
    debug(nn-flow);
    
    vector<int> nxt(nn+1),col(nn+1);
    for(int u=1,tot=0; u<=nn; ++u) {
        int s=u;
        while(s>=1 && s<=nn) {
            s=find_next(s);
            debug(s);
        }
        debug(u,s);
        if(s==-1) {
            col[u]=++tot;
            nxt[u]=-1;
        }else {
            nxt[u]=s-nn;
        }
    }
    if(n>1000) assert(0);
    for(int i=1; i<=nn; ++i) {
        if(col[i])
            continue;
        int j=i;
        while(col[j]==0)
            j=nxt[j];
        
        int c=col[j];
        for(j=i; col[j]==0; j=nxt[j])
            col[j]=c;
    }
    debug(nxt);

    for(int i=1; i<=n; ++i)
        cout<<col[Tarjan::color[i]]<<" ";
    return 0;
}
/*




*/

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 1ms
memory: 9552kb

input:

5 5
1 4
2 3
1 3
2 5
5 1

output:

2 1 1 2 2 

result:

ok AC

Test #2:

score: 0
Accepted
time: 1ms
memory: 3528kb

input:

5 7
1 2
2 1
4 3
5 1
5 4
4 1
4 5

output:

1 1 2 1 1 

result:

ok AC

Test #3:

score: 0
Accepted
time: 2ms
memory: 3532kb

input:

8 6
6 1
3 4
3 6
2 3
4 1
6 4

output:

1 1 1 1 2 1 3 4 

result:

ok AC

Test #4:

score: -100
Time Limit Exceeded

input:

7000 6999
4365 4296
2980 3141
6820 4995
4781 24
2416 5844
2940 2675
3293 2163
3853 5356
262 6706
1985 1497
5241 3803
353 1624
5838 4708
5452 3019
2029 6161
3849 4219
1095 1453
4268 4567
1184 1857
2911 3977
1662 2751
6353 6496
2002 6628
1407 4623
425 1331
4445 4277
1259 3165
4994 1044
2756 5788
5496 ...

output:


result: