CSES - Datatähti Open 2021 - Results
Submission details
Task:Sorting
Sender:ScarletS
Submission time:2021-01-30 20:58:36 +0200
Language:C++ (C++17)
Status:READY
Result:0
Feedback
groupverdictscore
#10
#20
Test results
testverdicttimegroup
#1ACCEPTED0.01 s1, 2details
#2--2details
#3ACCEPTED0.33 s1, 2details
#4--1, 2details

Code

#include <bits/stdc++.h>
#define ll long long
#define sz(x) (int)(x).size()
using namespace std;
int n;
set<vector<int>> s;
void dfs(vector<int> v)
{
if (s.find(v)!=s.end())
return;
s.insert(v);
for (int i=0;i+1<n;++i)
for (int j=i+2;j+1<n;++j)
{
swap(v[i],v[j]);
swap(v[i+1],v[j+1]);
dfs(v);
swap(v[i],v[j]);
swap(v[i+1],v[j+1]);
}
}
void solve()
{
cin>>n;
vector<int> v(n), w(n);
for (int i=0;i<n;++i)
cin>>v[i];
iota(w.begin(), w.end(), 1);
s.clear();
dfs(v);
if (s.find(w)==s.end())
cout<<"NO\n";
else
cout<<"YES\n";
}
int main()
{
ios_base::sync_with_stdio(0); cin.tie(0);
int tc;
cin>>tc;
while (tc--)
solve();
return 0;
}

Test details

Test 1

Group: 1, 2

Verdict: ACCEPTED

input
153
1
1
2
1 2
...

correct output
YES
YES
NO
NO
NO
...

user output
YES
YES
NO
NO
NO
...
Truncated

Test 2

Group: 2

Verdict:

input
1000
59
35 29 32 50 11 15 9 21 19 45 2...

correct output
YES
NO
YES
NO
YES
...

user output
(empty)

Test 3

Group: 1, 2

Verdict: ACCEPTED

input
720
6
1 6 4 5 2 3
6
6 3 2 1 5 4
...

correct output
YES
NO
NO
NO
YES
...

user output
YES
NO
NO
NO
YES
...
Truncated

Test 4

Group: 1, 2

Verdict:

input
1000
8
7 4 2 8 6 3 5 1
8
3 8 2 7 5 4 6 1
...

correct output
NO
NO
YES
NO
YES
...

user output
(empty)