CSES - Datatähti Open 2021 - Results
Submission details
Task:Sorting
Sender:voventa
Submission time:2021-01-31 14:50:48 +0200
Language:C++ (C++17)
Status:READY
Result:0
Feedback
groupverdictscore
#10
#20
Test results
testverdicttimegroup
#10.01 s1, 2details
#20.01 s2details
#30.01 s1, 2details
#40.01 s1, 2details

Code

#include <bits/stdc++.h>
#define X first
#define Y second
#define sz(a) (int)a.size()
#define pb push_back

using namespace std;
typedef long long ll;

void solve();

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int t = 1;
    cin >> t;
    while (t--)
        solve();
    return 0;
}

int a[110];
int b[110];

void solve() {
    int n;
    cin >> n;
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
        b[i] = a[i];
    }
    if (n > 10) {
        cout << "YES" << endl;
        return;
    }
    sort(b, b + n);
    for (int i = 0; i < n; ++i) {
        if (a[i] == b[i])
            continue;
        bool f = false;
        for (int j = i + 2; j < n - 1; ++j) {
            if (a[j] == b[i]) {
                swap(a[j], a[i]);
                swap(a[j + 1], a[i + 1]);
                f = true;
                break;
            }
        }
        if (!f) {
            if (b[i] == a[n - 1]) {
                if (n - 4 >= i) {
                    swap(a[n - 1], a[n - 3]);
                    swap(a[n - 2], a[n - 4]);
                    for (int j = i + 2; j < n - 1; ++j) {
                        if (a[j] == b[i]) {
                            swap(a[j], a[i]);
                            swap(a[j + 1], a[i + 1]);
                            f = true;
                            break;
                        }
                    }
                    if (!f) {
                        break;
                    }
                } else {
                    break;
                }
            } else {
                if (n - 4 >= i) {
                    swap(a[i], a[i + 2]);
                    swap(a[i + 1], a[i + 3]);
                    for (int j = i + 2; j < n - 1; ++j) {
                        if (a[j] == b[i]) {
                            swap(a[j], a[i]);
                            swap(a[j + 1], a[i + 1]);
                            f = true;
                            break;
                        }
                    }
                    if (!f) {
                        break;
                    }
                } else {
                    break;
                }
            }
        }
    }
    for (int i = n - 1; i >= 0; --i) {
        if (a[i] == b[i])
            continue;
        bool f = false;
        for (int j = i - 2; j >= 1; --j) {
            if (a[j] == b[i]) {
                swap(a[j], a[i]);
                swap(a[j - 1], a[i - 1]);
                f = true;
                break;
            }
        }
        if (!f) {
            if (b[i] == a[0]) {
                if (i <= 3) {
                    swap(a[0], a[2]);
                    swap(a[1], a[3]);
                    for (int j = i - 2; j >= 1; --j) {
                        if (a[j] == b[i]) {
                            swap(a[j], a[i]);
                            swap(a[j - 1], a[i - 1]);
                            f = true;
                            break;
                        }
                    }
                    if (!f) {
                        break;
                    }
                } else {
                    break;
                }
            } else {
                if (i >= 3) {
                    swap(a[i], a[i - 2]);
                    swap(a[i - 1], a[i - 3]);
                    for (int j = i - 2; j >= 1; --j) {
                        if (a[j] == b[i]) {
                            swap(a[j], a[i]);
                            swap(a[j - 1], a[i - 1]);
                            f = true;
                            break;
                        }
                    }
                    if (!f) {
                        break;
                    }
                } else {
                    break;
                }
            }
        }
    }
    bool pans = true;
    for (int i= 0; i < n; ++i) {
        if (a[i] != b[i])
            pans = false;
    }
    if (pans)
        cout << "YES" << endl;
    else
        cout << "NO" << endl;
    return;
}

Test details

Test 1

Group: 1, 2

Verdict:

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
YES
YES
YES
YES
YES
...
Truncated

Test 3

Group: 1, 2

Verdict:

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
NO
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
NO
NO
NO
NO
NO
...
Truncated