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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#97647#6329. Colorful GraphyangjlWA 4ms14892kbC++204.5kb2023-04-17 18:52:042023-04-17 18:52:08

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.
  • [2023-04-17 18:52:08]
  • 评测
  • 测评结果:WA
  • 用时:4ms
  • 内存:14892kb
  • [2023-04-17 18:52:04]
  • 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;
namespace Graph {
	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 n,m;
int dfn[N], low[N], dn;
int sta[N], insta[N], top;
int color[N], cn;
void tarjan(int u) {
	using namespace Graph;
	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);
}

namespace NetFlow {
    using T=int;
	const T INF=T(1)<<(sizeof(T)*8-2);
    const int _V=N;
    const int _E=1000000*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;
	}
    void printGraph() {
        auto dot=[&](int u)->string{
            if(u==s0) return "S";
            if(u==t0) return "T";
            return to_string(u);
        };
		cerr<<endl<<"Graph with "<<en<<" edges:"<<endl;
        for(int i=0; i<en; ++i) {
            int u=edge[i^1].t, v=edge[i].t;
            T w=edge[i].l;
            cerr<<dot(u)<<" -> "<<dot(v)<<" : ";
            cerr<<(w==INF?"INF":to_string(w))<<endl;
        }
    }
}

int main() {
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    cin>>n>>m;
    Graph::initGraph(n);
    vector<pair<int,int>> edg;
    while(m--) {
        int u,v;
        cin>>u>>v;
        Graph::addEdge(u,v);
        edg.emplace_back(u,v);
    }
    converge(n);
	debug_n(color+1,n);
    
    // 缩点之后跑网络流
	using namespace NetFlow;
	initGraph();
	for(int i=1; i<=cn; ++i) {
		addEdge(s0,i+cn,1);
		addEdge(i,t0,1);
	}
	for(auto [u,v]:edg) {
		int x=color[u];
		int y=color[v];
		if(x==y) continue;
		addEdge(x+cn,y,1);
		addEdge(x+cn,y+cn,1);// 向所有能到的点连边
	}

	int flow=dinic(s0,t0);

	vector<int> paint(cn+1);
	for(int u=1,c=0; u<=cn; ++u) {
		// 找前驱
		int flag=0;
		for(int i=head[u]; ~i; i=edge[i].next) {
			int v=edge[i].t;
			auto w=edge[i].l;
			if(v!=s0 && (i&1) && w==1) {
				flag=1;
				break;
			}
		}
		if(flag) continue;
		// debug(u);

		// 没有前驱,标颜色
		paint[u]=++c;
		for(int now=u; now;) {
			debug(now);
			int nxt=0;
			for(int i=head[now+cn]; ~i; i=edge[i].next) {
				if(i&1) continue;
				int v=edge[i].t, w=edge[i].l;
				if(w==1) continue;
				debug(now,v);

				// vis[i]=1;
				head[now+cn]=edge[i].next;
				if(v>cn) {
					nxt=v-cn;
				}else {
					paint[v]=c;
					nxt=v;
				}
				break;
			}
			now=nxt;
		}
	}

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




*/

Details

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Test #1:

score: 100
Accepted
time: 3ms
memory: 12296kb

input:

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

output:

2 2 2 1 2 

result:

ok AC

Test #2:

score: 0
Accepted
time: 4ms
memory: 12396kb

input:

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

output:

2 2 1 2 2 

result:

ok AC

Test #3:

score: 0
Accepted
time: 2ms
memory: 10292kb

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
Wrong Answer
time: 2ms
memory: 14892kb

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:

1749 1552 914 1362 2116 1750 1751 989 456 1260 2157 3126 1752 3342 1288 1753 724 1754 360 1710 761 590 3364 1246 1562 1755 1756 2503 1071 1757 580 637 1758 1759 973 974 1170 1760 3388 1761 1298 545 1762 694 1763 388 1764 2439 1765 1766 12 1767 838 3144 1526 1388 2649 1768 295 1769 618 2935 2015 2294...

result:

wrong answer Integer 2116 violates the range [1, 1750]