CSES - NOI 2019 Open - Results
Submission details
Task:Graph Ordering
Sender:eriksuenderhauf
Submission time:2019-03-07 20:14:36
Language:C++
Status:READY
Result:0
Feedback
groupverdictscore
#10
#20
#30
#40
#50
Test results
testverdicttimegroup
#10.07 s1, 4, 5details
#20.07 s1, 5details
#30.09 s1, 5details
#40.09 s1, 5details
#50.08 s1, 5details
#6ACCEPTED0.10 s2, 3, 5details
#7ACCEPTED0.10 s2, 3, 5details
#80.10 s2, 3, 4, 5details
#90.11 s2, 3, 4, 5details
#100.11 s2, 3, 4, 5details
#110.11 s2, 3, 5details
#120.10 s2, 3, 5details
#130.11 s2, 3, 4, 5details
#140.11 s2, 3, 4, 5details
#150.10 s2, 3, 4, 5details
#160.10 s2, 3, 4, 5details
#170.10 s2, 3, 4, 5details
#180.10 s2, 3, 4, 5details
#190.36 s3, 4, 5details
#200.37 s3, 4, 5details
#210.39 s3, 4, 5details
#220.36 s3, 4, 5details
#230.34 s3, 5details
#240.35 s3, 5details
#25ACCEPTED0.40 s3, 5details
#26ACCEPTED0.33 s3, 5details
#270.36 s3, 5details
#280.08 s5details
#290.07 s5details
#300.08 s4, 5details
#310.08 s4, 5details
#320.09 s4, 5details
#330.08 s4, 5details
#340.09 s5details
#350.08 s5details
#360.08 s5details
#37ACCEPTED0.07 s1, 2, 3, 4, 5details
#38ACCEPTED0.09 s2, 3, 5details
#39ACCEPTED0.08 s2, 3, 5details
#40ACCEPTED0.07 s2, 3, 5details
#41ACCEPTED0.07 s1, 2, 3, 5details
#420.08 s2, 3, 5details
#430.38 s3, 4, 5details
#440.37 s3, 4, 5details
#450.11 s2, 3, 4, 5details
#460.10 s2, 3, 4, 5details
#470.09 s2, 3, 5details
#480.34 s3, 4, 5details
#490.08 s4, 5details

Compiler report

input/code.cpp: In function 'int main()':
input/code.cpp:105:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &n, &m);
     ~~~~~^~~~~~~~~~~~~~~~~
input/code.cpp:109:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &u, &v);
         ~~~~~^~~~~~~~~~~~~~~~~

Code

//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define enl printf("\n")
#define case(t) printf("Case #%d: ", (t))
#define ni(n) scanf("%d", &(n))
#define nl(n) scanf("%lld", &(n))
#define nai(a, n) for (int i = 0; i < (n); i++) ni(a[i])
#define nal(a, n) for (int i = 0; i < (n); i++) nl(a[i])
#define pri(n) printf("%d\n", (n))
#define prl(n) printf("%lld\n", (n))
#define pii pair<int, int>
#define pil pair<int, long long>
#define pll pair<long long, long long>
#define vii vector<pii>
#define vil vector<pil>
#define vll vector<pll>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef cc_hash_table<int,int,hash<int>> ht;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> oset;
const double pi = acos(-1);
const int MOD = 1e9 + 7;
const int INF = 1e9 + 7;
const int MAXN = 1e6 + 5;
const double eps = 1e-9;
int vis[MAXN], ap[MAXN], rev[MAXN];
vi adj[MAXN];

void dfs(int u) {
    vis[u] = 1;
    for (int v: adj[u])
        if (!vis[v])
            dfs(v);
}
vi comp[MAXN], adj2[MAXN];
vi sol[MAXN];

void dfs2(int u, int c) {
    vis[u] = c;
    rev[u] = c;
    comp[c].pb(u);
    for (int v: adj[u])
        if (!vis[v] && !ap[v])
            dfs2(v, c);
}

vi ans;
int i2[MAXN];
int abc = 0;

void dfs3(int u, int p, int st) {
    int nx = st;
    abc++;
    if (comp[u].size() != 1) {
        deque<int> pq;
        pq.push_back(st);
        while (!pq.empty()) {
            int x = pq.front(); pq.pop_front();
            vis[x] = 1;
            ans.pb(x);
            i2[x] = ans.size()-1;
            for (int y: adj[x]) {
                if (rev[y] != rev[x]) continue;
                if (vis[y] == 1) continue;
                vis[y] = 1;
                pq.push_back(y);
            }
        }
    } else {
        //printf("%d ", comp[u][0]+1);
        ans.pb(comp[u][0]);
        i2[comp[u][0]] = ans.size()-1;
        for (int v: adj[comp[u][0]])
            if (!vis[v])
                nx = v;
    }
    for (int v: adj2[u])
        if (v != p)
            dfs3(v, u, nx);
}

int findP(int x, int y, int i) {
    if (x == y) return 1;
    for (int v: adj[x]) {
        if (i2[v] > i2[x]) {
            int r = findP(v, y, i);
            if (r == 1) return 1;
        }
    }
    return 0;
}

int main()
{
    int n, m;
    scanf("%d %d", &n, &m);
    if (n > 2000) return -1;
    for (int i = 0; i < m; i++) {
        int u, v;
        scanf("%d %d", &u, &v);
        u--, v--;
        adj[u].pb(v);
        adj[v].pb(u);
    }
    for (int i = 0; i < n; i++) {
        memset(vis, 0, sizeof vis);
        vis[i] = 1;
        int cnt = 0;
        for (int v: adj[i])
            if (!vis[v])
                dfs(v), cnt++;
        if (cnt > 1) ap[i] = 1;
        //if (cnt > 2) return !printf("IMPOSSIBLE\n");
        //if (cnt == 2) ap[i] = 1;
    }
    memset(vis, 0, sizeof vis);
    int cnt = 0;
    for (int i = 0; i < n; i++) {
        if (ap[i]) {
            vis[i] = ++cnt;
            rev[i] = cnt;
            comp[cnt].pb(i);
            continue;
        }
        if (vis[i] != 0) continue;
        dfs2(i, ++cnt);
    }
    for (int i = 0; i < n; i++) {
        for (int v: adj[i]) {
            if (rev[i] == rev[v]) continue;
            adj2[rev[i]].pb(rev[v]);
            adj2[rev[v]].pb(rev[i]);
        }
    }
    int sm = 0;
    for (int i = 1; i <= cnt; i++) {
        sm += comp[i].size();
        sort(adj2[i].begin(), adj2[i].end());
        adj2[i].erase(unique(adj2[i].begin(), adj2[i].end()), adj2[i].end());
        if (adj2[i].size() > 2) return !printf("IMPOSSIBLE\n");
    }
    /*memset(vis, 0, sizeof vis);
    for (int i = 0; i < n; i++) {
        if (ap[i] != 1) continue;
        vis[i] = 1;
    }
    for (int i = 0; i < n; i++) {
        if (ap[i] != 1) continue;
        for (int x: adj[i]) {
            if (vis[x]) continue;
            deque<int> pq;
            pq.push_back(x);
            while (!pq.empty()) {

            }
        }
    }*/
    memset(vis, 0, sizeof vis);
    for (int i = 1; i <= cnt; i++) {
        if (adj2[i].size() == 1) {
            dfs3(i, -1, comp[i][0]);
            break;
        }
    }
    if (abc != cnt) {
        if (!ans.empty()) return -1;
        deque<int> pq;
        pq.push_back(0);
        while (!pq.empty()) {
            int x = pq.front(); pq.pop_front();
            vis[x] = 1;
            ans.pb(x);
            i2[x] = ans.size()-1;
            for (int y: adj[x]) {
                if (rev[y] != rev[x]) continue;
                if (vis[y] == 1) continue;
                vis[y] = 1;
                pq.push_back(y);
            }
        }
    }
    /*for (int i: ans) {
        int ret = findP(ans[0], i, i);
        if (ret == 0)
            return -1;
    }
    for (int i: ans) {
        int ret = findP(ans[i], ans.back(), ans.back());
        if (ret == 0)
            return -1;
    }
    if (ans.size() != n) return -1;*/
    for (int i: ans) printf("%d ", i + 1);
    enl;
    return 0;
}

Test details

Test 1

Group: 1, 4, 5

Verdict:

input
100000 99999
8326 74462
11810 58064
21677 73087
62986 25005
...

correct output
1 44159 25721 84659 90058 9960...

user output
(empty)

Test 2

Group: 1, 5

Verdict:

input
100000 99999
28990 31200
86271 56882
61089 18658
52422 57504
...

correct output
68068 86325 91398 75677 51068 ...

user output
(empty)

Test 3

Group: 1, 5

Verdict:

input
100000 99999
29378 80094
12282 29378
96138 29378
61870 29378
...

correct output
IMPOSSIBLE

user output
(empty)

Test 4

Group: 1, 5

Verdict:

input
100000 99999
97935 71091
9181 31715
73649 47675
45394 25464
...

correct output
IMPOSSIBLE

user output
(empty)

Test 5

Group: 1, 5

Verdict:

input
100000 99999
2897 55594
11759 89041
56061 8717
69672 73046
...

correct output
IMPOSSIBLE

user output
(empty)

Test 6

Group: 2, 3, 5

Verdict: ACCEPTED

input
100 200
55 10
33 57
68 39
29 27
...

correct output
IMPOSSIBLE

user output
IMPOSSIBLE

Test 7

Group: 2, 3, 5

Verdict: ACCEPTED

input
100 175
71 86
100 88
83 92
25 73
...

correct output
IMPOSSIBLE

user output
IMPOSSIBLE

Test 8

Group: 2, 3, 4, 5

Verdict:

input
100 200
26 58
49 25
66 20
20 85
...

correct output
1 2 86 60 34 92 23 4 44 89 76 ...

user output
1 32 2 49 83 64 29 26 10 87 58...

Test 9

Group: 2, 3, 4, 5

Verdict:

input
100 195
19 28
63 48
1 57
1 20
...

correct output
12 97 18 74 36 10 78 50 61 95 ...

user output
1 57 20 11 23 13 88 53 99 56 4...

Test 10

Group: 2, 3, 4, 5

Verdict:

input
100 193
48 66
15 67
32 14
36 78
...

correct output
1 56 13 32 14 49 75 93 18 6 54...

user output
1 12 7 56 17 21 39 2 41 59 27 ...

Test 11

Group: 2, 3, 5

Verdict:

input
100 195
47 68
57 61
45 17
80 61
...

correct output
57 20 83 41 25 33 60 91 59 7 7...

user output
IMPOSSIBLE

Test 12

Group: 2, 3, 5

Verdict:

input
100 185
43 78
76 99
78 39
83 61
...

correct output
78 43 32 88 26 28 64 81 7 72 2...

user output
IMPOSSIBLE

Test 13

Group: 2, 3, 4, 5

Verdict:

input
99 132
96 16
18 89
98 50
66 26
...

correct output
1 12 45 71 97 22 35 9 60 27 20...

user output
IMPOSSIBLE

Test 14

Group: 2, 3, 4, 5

Verdict:

input
98 144
25 6
30 34
58 25
31 41
...

correct output
32 7 92 1 63 86 87 14 90 17 81...

user output
IMPOSSIBLE

Test 15

Group: 2, 3, 4, 5

Verdict:

input
96 145
19 70
72 92
27 72
17 85
...

correct output
1 50 30 4 10 48 42 5 70 19 29 ...

user output
IMPOSSIBLE

Test 16

Group: 2, 3, 4, 5

Verdict:

input
96 158
79 74
41 70
8 5
73 90
...

correct output
7 59 44 27 1 30 49 28 80 52 15...

user output
IMPOSSIBLE

Test 17

Group: 2, 3, 4, 5

Verdict:

input
96 142
95 35
67 89
91 70
48 21
...

correct output
13 20 81 33 1 51 19 69 16 85 6...

user output
IMPOSSIBLE

Test 18

Group: 2, 3, 4, 5

Verdict:

input
72 111
70 17
25 3
58 24
52 9
...

correct output
21 59 48 8 1 2 31 10 11 41 4 5...

user output
IMPOSSIBLE

Test 19

Group: 3, 4, 5

Verdict:

input
988 1563
402 701
830 801
50 578
8 144
...

correct output
1 136 368 683 447 304 131 53 8...

user output
IMPOSSIBLE

Test 20

Group: 3, 4, 5

Verdict:

input
994 1555
171 541
66 915
330 350
494 251
...

correct output
1 164 205 151 951 797 4 654 14...

user output
IMPOSSIBLE

Test 21

Group: 3, 4, 5

Verdict:

input
1000 2000
711 947
775 441
691 471
844 28
...

correct output
1 676 731 662 248 31 165 558 8...

user output
1 176 761 788 860 676 217 17 6...

Test 22

Group: 3, 4, 5

Verdict:

input
1000 2000
811 889
873 984
83 52
144 511
...

correct output
60 909 522 568 40 77 181 441 8...

user output
1 46 499 244 60 903 156 606 47...

Test 23

Group: 3, 5

Verdict:

input
1000 1869
625 715
448 714
110 927
432 1000
...

correct output
224 326 221 30 76 475 666 694 ...

user output
IMPOSSIBLE

Test 24

Group: 3, 5

Verdict:

input
1000 1783
709 1
182 768
355 40
786 260
...

correct output
230 6 135 678 346 19 470 960 3...

user output
IMPOSSIBLE

Test 25

Group: 3, 5

Verdict: ACCEPTED

input
1000 2000
92 876
273 598
287 535
526 972
...

correct output
IMPOSSIBLE

user output
IMPOSSIBLE

Test 26

Group: 3, 5

Verdict: ACCEPTED

input
1000 1910
789 821
553 740
889 527
488 730
...

correct output
IMPOSSIBLE

user output
IMPOSSIBLE

Test 27

Group: 3, 5

Verdict:

input
1000 1608
910 416
503 898
928 14
412 903
...

correct output
140 404 739 563 63 794 623 948...

user output
IMPOSSIBLE

Test 28

Group: 5

Verdict:

input
100000 198666
5659 89691
91040 53375
96642 56177
28768 57001
...

correct output
45598 74078 1039 83702 16344 8...

user output
(empty)

Test 29

Group: 5

Verdict:

input
100000 197194
41636 91770
63018 23827
39207 93713
67765 47715
...

correct output
79054 61855 53279 55546 60860 ...

user output
(empty)

Test 30

Group: 4, 5

Verdict:

input
100000 199985
13674 42886
51349 6858
78502 18751
13628 65936
...

correct output
17857 81664 4369 61462 79754 8...

user output
(empty)

Test 31

Group: 4, 5

Verdict:

input
100000 200000
27666 33166
7161 81452
73134 30281
5106 29308
...

correct output
76869 5635 23236 12666 61633 8...

user output
(empty)

Test 32

Group: 4, 5

Verdict:

input
100000 200000
62814 54729
98407 26888
91808 70132
58916 49730
...

correct output
19788 11202 3496 24237 68564 5...

user output
(empty)

Test 33

Group: 4, 5

Verdict:

input
100000 200000
2299 91653
21125 75544
54029 94067
86513 45051
...

correct output
1 20339 9304 40427 67694 95656...

user output
(empty)

Test 34

Group: 5

Verdict:

input
100000 200000
34688 93668
78127 18902
55150 33116
273 88797
...

correct output
IMPOSSIBLE

user output
(empty)

Test 35

Group: 5

Verdict:

input
100000 200000
21026 14630
5605 59639
25604 78683
55713 70513
...

correct output
IMPOSSIBLE

user output
(empty)

Test 36

Group: 5

Verdict:

input
100000 200000
63190 73606
52072 54105
22092 31495
9189 37924
...

correct output
IMPOSSIBLE

user output
(empty)

Test 37

Group: 1, 2, 3, 4, 5

Verdict: ACCEPTED

input
2 1
2 1

correct output
1 2

user output
1 2 

Test 38

Group: 2, 3, 5

Verdict: ACCEPTED

input
7 9
1 2
1 3
2 3
1 4
...

correct output
IMPOSSIBLE

user output
IMPOSSIBLE

Test 39

Group: 2, 3, 5

Verdict: ACCEPTED

input
9 12
1 2
2 3
3 1
4 5
...

correct output
IMPOSSIBLE

user output
IMPOSSIBLE

Test 40

Group: 2, 3, 5

Verdict: ACCEPTED

input
5 5
4 2
4 3
2 1
3 1
...

correct output
4 2 3 1 5

user output
2 4 3 1 5 

Test 41

Group: 1, 2, 3, 5

Verdict: ACCEPTED

input
4 3
1 2
3 2
4 2

correct output
IMPOSSIBLE

user output
IMPOSSIBLE

Test 42

Group: 2, 3, 5

Verdict:

input
17 30
4 1
3 14
6 16
13 6
...

correct output
7 8 11 15 1 2 9 3 14 13 5 10 1...

user output
2 5 9 16 10 12 17 3 6 14 13 4 ...

Test 43

Group: 3, 4, 5

Verdict:

input
992 1712
377 709
847 640
261 902
761 693
...

correct output
870 1 925 928 950 257 766 520 ...

user output
IMPOSSIBLE

Test 44

Group: 3, 4, 5

Verdict:

input
990 1672
305 445
800 155
365 779
824 247
...

correct output
108 461 160 696 895 655 376 21...

user output
IMPOSSIBLE

Test 45

Group: 2, 3, 4, 5

Verdict:

input
99 169
35 32
97 43
22 62
33 7
...

correct output
19 70 62 22 54 78 25 14 3 81 1...

user output
IMPOSSIBLE

Test 46

Group: 2, 3, 4, 5

Verdict:

input
99 164
62 73
19 35
55 92
79 91
...

correct output
21 25 64 90 17 15 89 95 70 33 ...

user output
IMPOSSIBLE

Test 47

Group: 2, 3, 5

Verdict:

input
53 68
7 46
51 14
3 18
8 40
...

correct output
32 30 38 33 27 12 8 20 2 34 45...

user output
1 51 28 14 13 38 32 50 17 25 5...

Test 48

Group: 3, 4, 5

Verdict:

input
996 1902
661 201
19 613
895 438
180 32
...

correct output
220 795 198 239 40 164 773 834...

user output
IMPOSSIBLE

Test 49

Group: 4, 5

Verdict:

input
6110 11528
3366 4718
3226 2188
5022 1186
3205 5349
...

correct output
1 2527 2211 554 4201 4522 1494...

user output
(empty)