結果

問題 No.1479 Matrix Eraser
ユーザー kakel-sankakel-san
提出日時 2024-07-04 23:55:43
言語 C#
(.NET 8.0.203)
結果
AC  
実行時間 882 ms / 3,000 ms
コード長 7,661 bytes
コンパイル時間 16,722 ms
コンパイル使用メモリ 169,560 KB
実行使用メモリ 209,104 KB
最終ジャッジ日時 2024-07-04 23:56:24
合計ジャッジ時間 40,816 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge2
このコードへのチャレンジ
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 88 ms
51,324 KB
testcase_01 AC 87 ms
51,288 KB
testcase_02 AC 91 ms
51,200 KB
testcase_03 AC 88 ms
51,284 KB
testcase_04 AC 87 ms
51,256 KB
testcase_05 AC 85 ms
51,156 KB
testcase_06 AC 88 ms
51,280 KB
testcase_07 AC 242 ms
86,240 KB
testcase_08 AC 304 ms
86,264 KB
testcase_09 AC 555 ms
87,812 KB
testcase_10 AC 756 ms
94,720 KB
testcase_11 AC 577 ms
87,728 KB
testcase_12 AC 265 ms
86,140 KB
testcase_13 AC 304 ms
86,272 KB
testcase_14 AC 272 ms
86,272 KB
testcase_15 AC 147 ms
67,200 KB
testcase_16 AC 282 ms
86,272 KB
testcase_17 AC 870 ms
98,372 KB
testcase_18 AC 861 ms
98,560 KB
testcase_19 AC 873 ms
98,556 KB
testcase_20 AC 842 ms
98,628 KB
testcase_21 AC 868 ms
98,468 KB
testcase_22 AC 874 ms
98,628 KB
testcase_23 AC 852 ms
98,372 KB
testcase_24 AC 882 ms
98,688 KB
testcase_25 AC 866 ms
98,500 KB
testcase_26 AC 872 ms
98,496 KB
testcase_27 AC 420 ms
83,936 KB
testcase_28 AC 451 ms
83,896 KB
testcase_29 AC 428 ms
83,968 KB
testcase_30 AC 430 ms
84,096 KB
testcase_31 AC 426 ms
83,932 KB
testcase_32 AC 805 ms
87,296 KB
testcase_33 AC 788 ms
87,176 KB
testcase_34 AC 778 ms
87,296 KB
testcase_35 AC 793 ms
87,296 KB
testcase_36 AC 799 ms
87,436 KB
testcase_37 AC 144 ms
70,796 KB
testcase_38 AC 484 ms
84,076 KB
testcase_39 AC 858 ms
98,492 KB
testcase_40 AC 89 ms
209,104 KB
権限があれば一括ダウンロードができます
コンパイルメッセージ
  復元対象のプロジェクトを決定しています...
  /home/judge/data/code/main.csproj を復元しました (95 ms)。
MSBuild のバージョン 17.9.6+a4ecab324 (.NET)
  main -> /home/judge/data/code/bin/Release/net8.0/main.dll
  main -> /home/judge/data/code/bin/Release/net8.0/publish/

ソースコード

diff # 

using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var (h, w) = (c[0], c[1]);
        var a = NArr(h);
        var dic = new List<(int x, int y)>[500_001];
        for (var i = 0; i < dic.Length; ++i) dic[i] = new List<(int x, int y)>();
        for (var i = 0; i < h; ++i) for (var j = 0; j < w; ++j)
        {
            dic[a[i][j]].Add((i, j));
        }
        var ans = 0L;
        for (var i = 500000; i > 0; --i) if (dic[i].Count > 0)
        {
            var xset = new HashSet<int>();
            var yset = new HashSet<int>();
            foreach (var l in dic[i])
            {
                xset.Add(l.x);
                yset.Add(l.y);
            }
            var xlist = new List<int>(xset);
            var ylist = new List<int>(yset);
            var xdic = new Dictionary<int, int>();
            for (var j = 0; j < xlist.Count; ++j) xdic[xlist[j]] = j;
            var ydic = new Dictionary<int, int>();
            for (var j = 0; j < ylist.Count; ++j) ydic[ylist[j]] = j;
            var g = new MaxFlowGraph(xlist.Count + ylist.Count + 2);
            var s = xlist.Count + ylist.Count;
            for (var j = 0; j < xlist.Count; ++j)
            {
                g.AddEdge(s, j, 1);
            }
            for (var j = 0; j < ylist.Count; ++j)
            {
                g.AddEdge(j + xlist.Count, s + 1, 1);
            }
            foreach (var l in dic[i])
            {
                g.AddEdge(xdic[l.x], ydic[l.y] + xlist.Count, int.MaxValue);
            }
            var f = g.Flow(s, s + 1);
            ans += f;
        }
        WriteLine(ans);
    }
    // 最大フローグラフ
    // MaxFlowGraph(n) n:頂点数
    // AddEdge(from, to, cap) from,to:0-indexed cap:最大用量
    // Flow(from, to) 最大流量を求める 各辺の流量を変更
    // Flow(from, to, flowLimit)
    // MinCut(from) Flow(最小カット)実行後の残余グラフで各頂点への到達可能性を取得
    // GetEdge(i), GetEdges() 内部の辺の状態を取得
    // ChangeEdge(i, newCap, newFlow) 対象辺の流量を変更
    class MaxFlowGraph
    {
        int _n;
        long max = long.MaxValue;
        class EdgeI
        {
            public int to { get; private set; }
            public int rev { get; private set; }
            public long cap { get; set; }
            public EdgeI(int to, int rev, long cap)
            {
                this.to = to;
                this.rev = rev;
                this.cap = cap;
            }
        }
        List<KeyValuePair<int, int>> pos = new List<KeyValuePair<int, int>>();
        List<EdgeI>[] g;

        public MaxFlowGraph(int n)
        {
            _n = n;
            g = new List<EdgeI>[n];
            for (var i = 0; i < n; ++i) g[i] = new List<EdgeI>();
        }
        public int AddEdge(int from, int to, long cap)
        {
            var m = pos.Count;
            pos.Add(new KeyValuePair<int, int>(from, g[from].Count));
            g[from].Add(new EdgeI(to, g[to].Count, cap));
            g[to].Add(new EdgeI(from, g[from].Count - 1, 0));
            return m;
        }
        public class Edge
        {
            public int from { get; private set; }
            public int to { get; private set; }
            public long cap { get; private set; }
            public long flow { get; private set; }
            public Edge(int from, int to, long cap, long flow)
            {
                this.from = from;
                this.to = to;
                this.cap = cap;
                this.flow = flow;
            }
        }
        public Edge GetEdge(int i)
        {
            var m = pos.Count;
            var e = g[pos[i].Key][pos[i].Value];
            var re = g[e.to][e.rev];
            return new Edge(pos[i].Key, e.to, e.cap + re.cap, re.cap);
        }
        public List<Edge> GetEdges()
        {
            var m = pos.Count;
            var result = new List<Edge>();
            for (var i = 0; i < m; ++i) result.Add(GetEdge(i));
            return result;
        }
        public void ChangeEdge(int i, long new_cap, long new_flow)
        {
            var m = pos.Count;
            var e = g[pos[i].Key][pos[i].Value];
            var re = g[e.to][e.rev];
            e.cap = new_cap - new_flow;
            re.cap = new_flow;
        }
        public long Flow(int s, int t)
        {
            return Flow(s, t, max);
        }
        public long Flow(int s, int t, long limit)
        {
            var level = new int[_n];
            var iter = new int[_n];
            var que = new Queue<int>();
            void bfs()
            {
                for (var i = 0; i < _n; ++i) level[i] = -1;
                level[s] = 0;
                que.Clear();
                que.Enqueue(s);
                while (que.Count > 0)
                {
                    var v = que.Dequeue();
                    foreach (var e in g[v])
                    {
                        if (e.cap == 0 || level[e.to] >= 0) continue;
                        level[e.to] = level[v] + 1;
                        if (e.to == t) return;
                        que.Enqueue(e.to);
                    }
                }
            }
            long dfs(int v, long up)
            {
                if (v == s) return up;
                long res = 0;
                var level_v = level[v];
                for (var i = iter[v]; i < g[v].Count; ++i)
                {
                    var e = g[v][i];
                    if (level_v <= level[e.to] || g[e.to][e.rev].cap == 0) continue;
                    long d = dfs(e.to, Min(up - res, g[e.to][e.rev].cap));
                    if (d <= 0) continue;
                    g[v][i].cap += d;
                    g[e.to][e.rev].cap -= d;
                    res += d;
                    if (res == up) break;
                }
                return res;
            }
            long flow = 0;
            while (flow < limit)
            {
                bfs();
                if (level[t] == -1) break;
                for (var i = 0; i < iter.Length; ++i) iter[i] = 0;
                while (flow < limit)
                {
                    var f = dfs(t, limit - flow);
                    if (f == 0) break;
                    flow += f;
                }
            }
            return flow;
        }
        long Min(long a, long b)
        {
            return a.CompareTo(b) < 0 ? a : b;
        }
        public bool[] MinCut(int s)
        {
            var visited = new bool[_n];
            var que = new Queue<int>();
            que.Enqueue(s);
            while (que.Count > 0)
            {
                var p = que.Dequeue();
                visited[p] = true;
                foreach (var e in g[p])
                {
                    if (e.cap != 0 && !visited[e.to])
                    {
                        visited[e.to] = true;
                        que.Enqueue(e.to);
                    }
                }
            }
            return visited;
        }
    }
}
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