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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
#99031#6308. MagicAcestarTL 32ms15860kbC++141.4kb2023-04-21 09:01:412023-04-21 09:01:42

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.
  • [2023-04-21 09:01:42]
  • 评测
  • 测评结果:TL
  • 用时:32ms
  • 内存:15860kb
  • [2023-04-21 09:01:41]
  • 提交

answer

#include <bits/stdc++.h>

using namespace std;

const int N = 5005;

int n;
pair<int, int> a[N];
bitset<N << 1> g[N << 1];
int s, t;
int dep[N << 1];

bool bfs()
{
    memset(dep, 0, sizeof(dep));
    queue<int> que;
    dep[s] = 1, que.push(s);
    while(!que.empty())
    {
        int u = que.front(); que.pop();
        for(auto v = g[u]._Find_first(); v <= t; v = g[u]._Find_next(v))
            if(!dep[v]) dep[v] = dep[u] + 1, que.push(v);
    }
    return dep[t];
}

int dfs(int u, int in)
{
    if(u == t || !in) return in;
    int out = 0;
    for(auto v  = g[u]._Find_first(); v <= t; v = g[u]._Find_next(v))
    {
        if(dep[v] != dep[u] + 1) continue;
        int f = dfs(v, min(in, 1));
        if(f) g[u][v] = 0, g[v][u] = 1;
        in -= f, out += f;
        if(!in) break;
    }
    return out;
}

int dinic()
{
    int res = 0;
    while(bfs()) res += dfs(s, 1e9);
    return res;
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr), cout.tie(nullptr);

    cin >> n; s = 2 * n + 1, t = s + 1;
    for(int i = 1; i <= n; i++) cin >> a[i].first >> a[i].second;
    sort(a + 1, a + n + 1);
    for(int i = 1; i <= n; i++)
        for(int j = i + 1; j <= n; j++)
            if(a[j].first < a[i].second && a[i].second < a[j].second)
                g[j][n + i] = 1;
    for(int i = 1; i <= n; i++) g[s][i] = 1, g[n + i][t] = 1;

    cout << 2 * n - dinic() << '\n';
    return 0;
}

詳細信息

Test #1:

score: 100
Accepted
time: 2ms
memory: 3468kb

input:

5
2 3
6 7
1 9
5 10
4 8

output:

9

result:

ok 1 number(s): "9"

Test #2:

score: 0
Accepted
time: 8ms
memory: 15708kb

input:

5000
7985 7987
42 46
1591 1593
407 410
6305 6306
1456 1457
5874 5875
7135 7137
7041 7046
6813 6815
8868 8871
665 666
4055 4056
9789 9796
7067 7068
4745 4746
5167 5171
1735 1737
2125 2128
1444 1447
1348 1352
6087 6090
1381 1384
1600 1601
5187 5190
2801 2802
8449 8450
9376 9377
4021 4024
2674 2676
490...

output:

8134

result:

ok 1 number(s): "8134"

Test #3:

score: 0
Accepted
time: 13ms
memory: 15844kb

input:

5000
3171 3172
4062 4064
4647 4651
3670 3673
7112 7114
9714 9717
3781 3789
8422 8426
457 460
5450 5454
7113 7122
6313 6320
9969 9973
828 832
6878 6892
4476 4483
892 903
251 259
6304 6315
130 134
9206 9215
2679 2686
9090 9091
8222 8228
9374 9375
2985 2989
3397 3401
4916 4918
6819 6821
883 889
2516 25...

output:

7047

result:

ok 1 number(s): "7047"

Test #4:

score: 0
Accepted
time: 26ms
memory: 15860kb

input:

5000
7269 7286
1979 1990
4225 4241
7866 7872
2052 2067
1508 1514
2366 2370
3488 3493
8979 8987
302 306
6730 6732
7704 7705
5528 5544
7420 7425
4705 4712
593 601
6662 6668
5228 5257
2008 2013
548 562
7949 7950
1017 1020
1025 1028
6 11
4722 4736
9945 9950
8368 8379
6781 6787
4558 4566
400 404
858 864
...

output:

6191

result:

ok 1 number(s): "6191"

Test #5:

score: 0
Accepted
time: 32ms
memory: 15800kb

input:

5000
3005 3008
7811 7821
2832 2840
9812 9818
3947 3952
3629 3665
7443 7455
1473 1478
1467 1494
5499 5508
229 232
9477 9498
9500 9514
4769 4775
9488 9503
1514 1520
5101 5112
2455 2456
3558 3610
9072 9188
659 666
2286 2301
9735 9782
5959 5984
5823 5844
1827 1835
3658 3681
3494 3503
1016 1018
3418 3420...

output:

5636

result:

ok 1 number(s): "5636"

Test #6:

score: -100
Time Limit Exceeded

input:

5000
1017 1019
5731 5744
8592 8697
3414 3561
277 356
4421 4458
7969 7989
3733 3759
1975 1986
6895 6898
8580 8657
2320 2325
6494 6510
3574 3616
7721 7780
7756 7835
1744 1748
5085 5102
5428 5588
6823 6847
9348 9405
1969 2064
1152 1242
3676 3679
5569 5713
213 248
8277 8285
3739 3782
5582 5604
9076 9105...

output:


result: