CSES - Datatähti Open 2021

Submission details
Task:	Split in Three
Sender:	kenechi
Submission time:	2021-01-31 12:15:54 +0200
Language:	C++ (C++17)
Status:	READY
Result:	0

Feedback
group	verdict	score
#1	WRONG ANSWER	0
#2	WRONG ANSWER	0

Test results
test	verdict	time	group
#1	ACCEPTED	0.01 s	1, 2	details
#2	ACCEPTED	0.01 s	1, 2	details
#3	WRONG ANSWER	0.01 s	1, 2	details
#4	WRONG ANSWER	0.01 s	1, 2	details
#5	ACCEPTED	0.01 s	1, 2	details
#6	WRONG ANSWER	0.01 s	1, 2	details
#7	WRONG ANSWER	0.01 s	1, 2	details
#8	ACCEPTED	0.01 s	1, 2	details
#9	WRONG ANSWER	0.01 s	2	details
#10	WRONG ANSWER	0.01 s	2	details
#11	WRONG ANSWER	0.01 s	2	details
#12	ACCEPTED	0.01 s	2	details
#13	WRONG ANSWER	0.01 s	2	details
#14	WRONG ANSWER	0.01 s	2	details
#15	ACCEPTED	0.01 s	2	details

Code

#include <bits/stdc++.h>

using namespace std;

#define int long long
#define endl '\n'
#define maxn 200010
const int MOD = 1000000007;

void solve() {
    int n;
    cin >> n;

    // x - 1
    // x
    // x + 1

    // 3 * x = n * (n + 1) // 2

    // n * (n + 1) // 6

    int tp = n * (n + 1);
    if (tp % 6) {
        cout << "IMPOSSIBLE";
        return;
    }
    vector<int> v1, v2;
    int sum = 0, val = tp / 6 + 1;
    for (int i = n; i >= 1 and sum < val; i--) {
        if (sum + i <= val)sum += i, v1.push_back(i);
        else {
            int back = val - sum;
            if (back < i) {
                v1.push_back(back);
                break;
            } else {
                cout << "IMPOSSIBLE";
                return;
            }
        }
    }
    val--;
    sum = 0;
    for (int i = n; i >= 1 and sum < val; i++) {
        if (binary_search(v1.begin(), v1.end(), i))continue;
        if (sum + i <= val)sum += i, v2.push_back(i);
        else {
            int back = val - sum;
            if (back <= n and !binary_search(v1.begin(), v1.end(), back, greater<int>())) {
                v2.push_back(back);
                break;
            } else {
                cout << "IMPOSSIBLE";
                return;
            }
        }
    }
    for (int i = 1; i <= n; i++) {
        if (binary_search(v1.begin(), v1.end(), i, greater<int>()))cout << 3 << " ";
        else if (binary_search(v2.begin(), v2.end(), i, greater<int>()))cout << 2 << " ";
        else cout << 1 << " ";
    }
}

int32_t main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int t = 1;
//    cin >> t;

    while (t--)
        solve();
    return 0;
}

Test details

Test 1

Group: 1, 2

Verdict: ACCEPTED

input
`3` view save

correct output
`1 2 3` view save

user output
`1 2 3` view save

Test 2

Group: 1, 2

Verdict: ACCEPTED

input
`4` view save

correct output
`IMPOSSIBLE` view save

user output
`IMPOSSIBLE` view save

Test 3

Group: 1, 2

Verdict: WRONG ANSWER

input
`5` view save

correct output
`1 3 1 3 2` view save

user output
`3 1 1 1 3` view save

Test 4

Group: 1, 2

Verdict: WRONG ANSWER

input
`6` view save

correct output
`1 3 2 2 1 3` view save

user output
`2 3 1 1 1 3` view save

Test 5

Group: 1, 2

Verdict: ACCEPTED

input
`7` view save

correct output
`IMPOSSIBLE` view save

user output
`IMPOSSIBLE` view save

Test 6

Group: 1, 2

Verdict: WRONG ANSWER

input
`8` view save

correct output
`2 3 1 2 3 3 2 1` view save

user output
`1 1 1 2 3 1 1 3` view save

Test 7

Group: 1, 2

Verdict: WRONG ANSWER

input
`9` view save

correct output
`1 2 3 1 2 3 3 2 1` view save

user output
`1 1 1 1 1 2 3 1 3` view save

Test 8

Group: 1, 2

Verdict: ACCEPTED

input
`10` view save

correct output
`IMPOSSIBLE` view save

user output
`IMPOSSIBLE` view save

Test 9

Group: 2

Verdict: WRONG ANSWER

input
`42` view save

correct output
`1 3 2 2 1 3 1 2 3 3 2 1 1 2 3 ...` view save

user output
`1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ...` view save

Test 10

Group: 2

Verdict: WRONG ANSWER

input
`95` view save

correct output
`1 3 1 3 2 1 2 3 3 2 1 1 2 3 3 ...` view save

user output
`IMPOSSIBLE` view save

Test 11

Group: 2

Verdict: WRONG ANSWER

input
`96` view save

correct output
`1 3 2 2 1 3 1 2 3 3 2 1 1 2 3 ...` view save

user output
`1 1 1 1 1 1 2 1 1 1 1 1 1 1 1 ...` Truncated

Test 12

Group: 2

Verdict: ACCEPTED

input
`97` view save

correct output
`IMPOSSIBLE` view save

user output
`IMPOSSIBLE` view save

Test 13

Group: 2

Verdict: WRONG ANSWER

input
`98` view save

correct output
`2 3 1 2 3 3 2 1 1 2 3 3 2 1 1 ...` view save

user output
`1 1 1 1 1 1 3 1 1 1 1 1 1 1 1 ...` Truncated

Test 14

Group: 2

Verdict: WRONG ANSWER

input
`99` view save

correct output
`1 2 3 1 2 3 3 2 1 1 2 3 3 2 1 ...` view save

user output
`1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ...` Truncated

Test 15

Group: 2

Verdict: ACCEPTED

input
`100` view save

correct output
`IMPOSSIBLE` view save

user output
`IMPOSSIBLE` view save

Datatähti Open 2021

Split in Three

Code

Test details

Test 1

Test 2

Test 3

Test 4

Test 5

Test 6

Test 7

Test 8

Test 9

Test 10

Test 11

Test 12

Test 13

Test 14

Test 15

Tasks

Submissions (kenechi)