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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#553706#6329. Colorful Graphucup-team3691#TL 0ms3672kbC++237.6kb2024-09-08 18:36:282024-09-08 18:36:29

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你现在查看的是最新测评结果

  • [2024-09-08 18:36:29]
  • 评测
  • 测评结果:TL
  • 用时:0ms
  • 内存:3672kb
  • [2024-09-08 18:36:28]
  • 提交

answer

#include <iostream>
#include <vector>
#include <queue>
#include <algorithm>
#include <map>
#include <ctime>
#include <random>
#include <cassert>

using namespace std;
using ll = long long;

const int mod = 998244353;

struct Edge {
    int nxt, flow, cap;
};

struct Flow {
    int n, total_flow;
    vector <vector <int>> G;
    vector <Edge> edge_list;
    int s, d;
    vector <int> prv;
    bool bfs() {
        queue <int> q;
        for (int i = 0; i < n; i++) {
            prv[i] = -1;
        }
        prv[s] = 0;
        q.push(s);
        while (!q.empty()) {
            int curr = q.front();
            q.pop();
            for (int edge_ind : G[curr]) {
                Edge curr_edge = edge_list[edge_ind];
                if (prv[curr_edge.nxt] == -1 && curr_edge.flow < curr_edge.cap) {
                    prv[curr_edge.nxt] = edge_ind;
                    q.push(curr_edge.nxt);
                }
            }
            if (prv[d] != -1) {
                return 1;
            }
        }
        return 0;
    }

    Flow(int _n) {
        n = _n;
        G.resize(n);
        prv.resize(n);
        s = 0;
        d = n - 1;
        total_flow = 0;
    }
    void addEdge(int x, int y, int cap) {
        edge_list.push_back({y, 0, cap});
        edge_list.push_back({x, 0, 0});
        G[x].push_back(edge_list.size() - 2);
        G[y].push_back(edge_list.size() - 1);
    }
    void pushFlow() {
        while (bfs()) {
            for (int edge_ind : G[d]) {
                int min_flow = 1e9;
                if (prv[edge_list[edge_ind].nxt] == -1) {
                    continue;
                }
                prv[d] = edge_ind^1;
                for (int nod = d; nod != s; nod = edge_list[prv[nod]^1].nxt) {
                    min_flow = min(min_flow, edge_list[prv[nod]].cap - edge_list[prv[nod]].flow);
                }
                for (int nod = d; nod != s; nod = edge_list[prv[nod]^1].nxt) {
                    edge_list[prv[nod]].flow += min_flow;
                    edge_list[prv[nod] ^ 1].flow -= min_flow;
                }
                total_flow += min_flow;
            }

        }
    }
    void dfsSolution(int nod, vector <int> &color, int c) {
        color[nod] = c;
        for (int edge_ind : G[2 * nod + 1]) {
            if (edge_list[edge_ind].flow <= 0) {
                continue;
            }
            if (edge_list[edge_ind].nxt == s || edge_list[edge_ind].nxt == d) {
                continue;
            }
            int nxt = (edge_list[edge_ind].nxt - 2) / 2;
            if (color[nxt] != c) {
                dfsSolution(nxt, color, c);
                return;
            }
        }
    }
    void afis() {
        for (int i = 0; i < edge_list.size(); i += 2) {
            if (edge_list[i].cap == 1) {
                continue;
            }
            if (edge_list[i].flow > 0) {
                cout << (edge_list[i ^ 1].nxt - 1) / 2 + 1 << ' ' << (edge_list[i].nxt - 2) / 2 + 1 << ' ' << edge_list[i].flow << ' ' << edge_list[i].cap << '\n';
            }
        }
    }

    vector <vector <pair <int, int>>> getDistrib(int nr) {
        vector <vector <pair <int, int>>> distribG(nr);
        for (int i = 0; i < edge_list.size(); i += 2) {
            if (edge_list[i].cap == 1) {
                continue;
            }
            if (edge_list[i].flow > 0) {
                distribG[(edge_list[i ^ 1].nxt - 1) / 2].push_back({(edge_list[i].nxt - 2) / 2, edge_list[i].flow});
                //cerr << (edge_list[i ^ 1].nxt - 1) / 2 << ' ' << (edge_list[i].nxt - 2) / 2 << ' ' << edge_list[i].flow << '\n';
            }
        }
        return distribG;
    }

    int getFlow() {
        return total_flow;
    }
};


struct Graph {
    int n, m, nrctc;
    vector <pair <int, int>> edges;
    vector <vector <int>> G, revG;
    vector <int> comp;
    void readGraph() {
        for (int i = 0; i < m; i++) {
            int x, y;
            cin >> x >> y;
            x--, y--;
            edges[i] = {x, y};
            G[x].push_back(y);
            revG[y].push_back(x);
        }
    }

    void dfs1(int nod, vector <int> &used, vector <int> &ordine) {
        used[nod] = 1;
        for (int nxt : G[nod]) {
            if (used[nxt]) {
                continue;
            }
            dfs1(nxt, used, ordine);
        }
        ordine.push_back(nod);
    }
    void dfs2(int nod, int c) {
        comp[nod] = c;
        for (int nxt : revG[nod]) {
            if (comp[nxt]) {
                continue;
            }
            dfs2(nxt, c);
        }
    }

    void computeScc() {
        vector <int> used(n, 0);
        vector <int> ordine;
        for (int i = 0; i < n; i++) {
            if (used[i]) {
                continue;
            }
            dfs1(i, used, ordine);
        }
        reverse(ordine.begin(), ordine.end());
        for (int i = 0; i < n; i++) {
            int nod = ordine[i];
            if (comp[nod]) {
                continue;
            }
            nrctc++;
            dfs2(nod, nrctc);
        }
    }

    vector <vector <int>> simplifyEdges() {
        vector <vector <int>> newG(nrctc, vector <int> ());
        for (auto [x, y] : edges) {
            if (comp[x] == comp[y]) {
                continue;
            }
            newG[comp[x] - 1].push_back(comp[y] - 1);
        }
        for (int i = 0; i < nrctc; i++) {
            sort(newG[i].begin(), newG[i].end());
            newG[i].erase(unique(newG[i].begin(), newG[i].end()), newG[i].end());
        }
        return newG;
    }

    void printSolution(vector <int> &color) {
        for (int i = 0; i < n; i++) {
            cout << color[comp[i] - 1] << ' ';
        }
    }

    Graph(int _n, int _m) {
        n = _n;
        m = _m;
        edges.resize(m);
        G.resize(n);
        revG.resize(n);
        comp.resize(n, 0);
        nrctc = 0;
    }
};

void solve() {
    int n, m;
    cin >> n >> m;
    Graph sccGraph(n, m);
    sccGraph.readGraph();
    sccGraph.computeScc();
    vector <vector <int>> G = sccGraph.simplifyEdges();
    n = sccGraph.nrctc;

    Flow flowGraph(2 * n + 2);
    for (int i = 0; i < n; i++) {
        flowGraph.addEdge(0, 2 * i + 1, 1);
        flowGraph.addEdge(2 * i + 2, 2 * n + 1, 1);
        flowGraph.addEdge(2 * i + 2, 2 * i + 1, 1e9);
        for (int x : G[i]) {
            flowGraph.addEdge(2 * i + 1, 2 * x + 2, 1e9);
        }
    }
    flowGraph.pushFlow();
    vector <vector <pair <int, int>>> distribG = flowGraph.getDistrib(n);
    vector <vector <int>> colors(n);
    int cnt = 0;
    for (int i = 0; i < n; i++) {
        if (colors[i].empty()) {
            cnt++;
            colors[i].push_back(cnt);
        }
        int poz = 0;
        for (auto [nod, demand] : distribG[i]) {
            for (int j = 0; j < demand; j++) {
                if (poz >= colors[i].size()) {
                    cnt++;
                    colors[i].push_back(cnt);
                }
                colors[nod].push_back(colors[i][poz]);
                poz++;
            }
        }
    }

    vector <int> color(n, 0);
    for (int i = 0; i < n; i++) {
        color[i] = colors[i][0];
    }
    sccGraph.printSolution(color);
}

signed main() {
#ifdef LOCAL
    freopen("test.in", "r", stdin);
    freopen("test.out", "w", stdout);
#endif // LOCAL
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int nrt = 1;
    //cin >> nrt;
    while (nrt--) {
        solve();
    }
    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 3568kb

input:

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

output:

1 1 2 1 1 

result:

ok AC

Test #2:

score: 0
Accepted
time: 0ms
memory: 3672kb

input:

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

output:

2 2 1 1 1 

result:

ok AC

Test #3:

score: 0
Accepted
time: 0ms
memory: 3552kb

input:

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

output:

4 4 4 4 3 4 2 1 

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: