CSES - Datatähti Open 2017 - Results
Submission details
Task:Tunnels
Sender:Xagak
Submission time:2017-01-21 15:55:21 +0200
Language:C++
Status:READY
Result:47
Feedback
groupverdictscore
#1ACCEPTED16
#2ACCEPTED31
#30
Test results
testverdicttimegroup
#1ACCEPTED0.04 s1details
#2ACCEPTED0.04 s1details
#3ACCEPTED0.04 s1details
#4ACCEPTED0.04 s1details
#5ACCEPTED0.05 s1details
#6ACCEPTED0.04 s2details
#7ACCEPTED0.04 s2details
#8ACCEPTED0.04 s2details
#9ACCEPTED0.03 s2details
#10ACCEPTED0.05 s2details
#11--3details
#12--3details
#13--3details
#14--3details
#15--3details

Code

#include <iostream>
#include <algorithm>
#include <set>
using namespace std;
set <int> s[100002];
set <int>::iterator it;
int q[100002];
int n,m;
void dfs(int gag,int ngag){
    if(ngag!=gag){
        m--;
        it=s[ngag].lower_bound(gag);
        s[ngag].erase(it);
        q[gag]--;
    }
    for(set <int> ::iterator it=s[gag].begin();it!=s[gag].end();it++){
        int to=*it;
        dfs(to,gag);
        return;
    }
}
int main(){
    cin>>n>>m;
    for(int i=0;i<m;i++){
        int j,k;
        cin>>j>>k;
        s[j].insert(k);
        q[k]++;
    }
    int ans=0;
    while(m>0){
        ans++;
        for(int j=1;j<=n;j++){
            if(q[j]==0 && s[j].size()>0){
                dfs(j,j);
                break;
            }
        }
    }
    cout<<ans<<endl;
    return 0;
}

Test details

Test 1

Group: 1

Verdict: ACCEPTED

input
10 20
4 5
6 4
5 1
5 9
...

correct output
11

user output
11

Test 2

Group: 1

Verdict: ACCEPTED

input
10 10
7 3
5 2
9 7
1 5
...

correct output
5

user output
5

Test 3

Group: 1

Verdict: ACCEPTED

input
10 5
5 7
3 8
5 8
3 7
...

correct output
4

user output
4

Test 4

Group: 1

Verdict: ACCEPTED

input
10 4
9 1
6 8
7 1
5 7

correct output
3

user output
3

Test 5

Group: 1

Verdict: ACCEPTED

input
10 2
10 6
2 1

correct output
2

user output
2

Test 6

Group: 2

Verdict: ACCEPTED

input
100 200
24 40
25 6
36 93
92 90
...

correct output
97

user output
97

Test 7

Group: 2

Verdict: ACCEPTED

input
100 100
98 37
91 37
60 92
46 27
...

correct output
60

user output
60

Test 8

Group: 2

Verdict: ACCEPTED

input
100 50
74 95
53 72
69 85
14 13
...

correct output
34

user output
34

Test 9

Group: 2

Verdict: ACCEPTED

input
100 40
28 76
10 81
13 52
46 83
...

correct output
29

user output
29

Test 10

Group: 2

Verdict: ACCEPTED

input
100 20
27 35
72 92
56 4
64 80
...

correct output
18

user output
18

Test 11

Group: 3

Verdict:

input
100000 200000
89244 59358
22943 56710
63331 89437
56581 38400
...

correct output
102510

user output
(empty)

Test 12

Group: 3

Verdict:

input
100000 100000
21701 85599
61542 21474
38081 29362
46316 64038
...

correct output
60593

user output
(empty)

Test 13

Group: 3

Verdict:

input
100000 50000
86469 4833
16351 35505
59315 33011
95464 16985
...

correct output
35933

user output
(empty)

Test 14

Group: 3

Verdict:

input
100000 40000
5392 23534
63204 45619
74330 25925
59678 88427
...

correct output
30074

user output
(empty)

Test 15

Group: 3

Verdict:

input
100000 20000
80156 16531
71753 77661
7028 33389
17168 646
...

correct output
16882

user output
(empty)