CSES - BOI 2026 Mirror Day 2

Submission details
Task:	Distances
Sender:	Sebastian
Submission time:	2026-04-17 10:00:10 +0300
Language:	C++ (C++20)
Status:	READY
Result:	100

Feedback
subtask	verdict	score
#1	ACCEPTED	11
#2	ACCEPTED	4
#3	ACCEPTED	6
#4	ACCEPTED	19
#5	ACCEPTED	22
#6	ACCEPTED	38

Test results
test	verdict	time	subtask
#1	ACCEPTED	0.01 s	1, 4, 6	details
#2	ACCEPTED	0.01 s	1, 2, 3, 4, 5, 6	details
#3	ACCEPTED	0.01 s	1, 3, 4, 5, 6	details
#4	ACCEPTED	0.01 s	1, 2, 4, 6	details
#5	ACCEPTED	0.01 s	1, 3, 4, 5, 6	details
#6	ACCEPTED	0.01 s	1, 4, 6	details
#7	ACCEPTED	0.01 s	1, 4, 6	details
#8	ACCEPTED	0.01 s	1, 2, 4, 6	details
#9	ACCEPTED	0.01 s	1, 3, 4, 5, 6	details
#10	ACCEPTED	0.01 s	1, 4, 5, 6	details
#11	ACCEPTED	0.01 s	1, 4, 6	details
#12	ACCEPTED	0.01 s	1, 4, 6	details
#13	ACCEPTED	0.01 s	1, 4, 6	details
#14	ACCEPTED	0.01 s	1, 6	details
#15	ACCEPTED	0.01 s	1, 2, 6	details
#16	ACCEPTED	0.01 s	4, 6	details
#17	ACCEPTED	0.01 s	4, 6	details
#18	ACCEPTED	0.01 s	3, 4, 5, 6	details
#19	ACCEPTED	0.01 s	4, 5, 6	details
#20	ACCEPTED	0.01 s	4, 5, 6	details
#21	ACCEPTED	0.01 s	5, 6	details
#22	ACCEPTED	0.01 s	5, 6	details
#23	ACCEPTED	0.01 s	2, 6	details
#24	ACCEPTED	0.01 s	3, 4, 5, 6	details
#25	ACCEPTED	0.01 s	4, 5, 6	details
#26	ACCEPTED	0.01 s	4, 5, 6	details
#27	ACCEPTED	0.01 s	5, 6	details
#28	ACCEPTED	0.01 s	5, 6	details
#29	ACCEPTED	0.01 s	2, 6	details
#30	ACCEPTED	0.01 s	3, 4, 5, 6	details
#31	ACCEPTED	0.01 s	4, 5, 6	details
#32	ACCEPTED	0.01 s	4, 5, 6	details
#33	ACCEPTED	0.01 s	4, 5, 6	details
#34	ACCEPTED	0.01 s	5, 6	details
#35	ACCEPTED	0.01 s	5, 6	details
#36	ACCEPTED	0.01 s	5, 6	details
#37	ACCEPTED	0.01 s	6	details
#38	ACCEPTED	0.01 s	6	details
#39	ACCEPTED	0.01 s	2, 6	details
#40	ACCEPTED	0.01 s	6	details
#41	ACCEPTED	0.01 s	6	details
#42	ACCEPTED	0.01 s	6	details
#43	ACCEPTED	0.01 s	6	details
#44	ACCEPTED	0.01 s	6	details

Code

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef __int128_t i128;
#define all(x) begin(x), end(x)
#define sz(x) ((int)(x).size())
const ll inf = 4e18;

bool is_square(ll x) {
    ll l = 1, r = x;
    while (l < r) {
        ll mid = l + (r - l + 1) / 2;
        if (mid * mid <= x) l = mid;
        else r = mid - 1;
    }
    return l * l == x;
}

void solve() {
    ll y = 720;
    vector<ll> yes = {0}, no = {};
    for (ll x = 1; sz(yes) < 100 || sz(no) < 100; x++) {
        vector<ll> &vec = (is_square(x * x + y * y) ? yes : no);
        vec.push_back(x);
        vec.push_back(-x);
    }
    yes.resize(100);
    no.resize(100);

    ll n, k; cin >> n >> k;

    vector<pll> res;

    ll t = 0;
    while (n > 1 && k <= (n-1) * (n-2) / 2) {
        t++;
        res.emplace_back(1000000000 - t, t);
        cout << 1000000000 - t << ' ' << t << '\n';
        n--;
    }
    if (k == n * (n-1) / 2) {
        for (ll i = 0; i < n; i++) {
            cout << i << " 0\n";
        }
        return;
    }
    
    k -= (n-1) * (n-2) / 2;
    n--;
    assert(k > 0 && k <= n);
    cout << "0 " << y << '\n';
    for (ll i = 0; i < k; i++) {
        cout << yes[i] << " 0\n";
    }
    for (ll i = k; i < n; i++) {
        cout << no[i] << " 0\n";
    }
}

int main(){
    cin.tie(0)->sync_with_stdio(0);
    solve();
}

Test details

Test 1

Subtask: 1, 4, 6

Verdict: ACCEPTED

input
`3 2` view save

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

user output
`0 720 0 0 -1 0` view save

Test 2

Subtask: 1, 2, 3, 4, 5, 6

Verdict: ACCEPTED

input
`1 0` view save

correct output
`1 0` view save

user output
`0 0` view save

Test 3

Subtask: 1, 3, 4, 5, 6

Verdict: ACCEPTED

input
`2 0` view save

correct output
`1 0 804289383 846930886` view save

user output
`999999999 1 0 0` view save

Test 4

Subtask: 1, 2, 4, 6

Verdict: ACCEPTED

input
`2 1` view save

correct output
`1 0 2 0` view save

user output
`0 0 1 0` view save

Test 5

Subtask: 1, 3, 4, 5, 6

Verdict: ACCEPTED

input
`3 0` view save

correct output
`1 0 804289383 846930886 681692777 714636915` view save

user output
`999999999 1 999999998 2 0 0` view save

Test 6

Subtask: 1, 4, 6

Verdict: ACCEPTED

input
`3 1` view save

correct output
`1 0 2 0 804289383 846930886` view save

user output
`999999999 1 0 0 1 0` view save

Test 7

Subtask: 1, 4, 6

Verdict: ACCEPTED

input
`3 2` view save

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

user output
`0 720 0 0 -1 0` view save

Test 8

Subtask: 1, 2, 4, 6

Verdict: ACCEPTED

input
`3 3` view save

correct output
`1 0 2 0 3 0` view save

user output
`0 0 1 0 2 0` view save

Test 9

Subtask: 1, 3, 4, 5, 6

Verdict: ACCEPTED

input
`4 0` view save

correct output
`1 0 804289383 846930886 681692777 714636915 957747793 424238335` view save

user output
`999999999 1 999999998 2 999999997 3 0 0` view save

Test 10

Subtask: 1, 4, 5, 6

Verdict: ACCEPTED

input
`4 1` view save

correct output
`1 0 2 0 804289383 846930886 681692777 714636915` view save

user output
`999999999 1 999999998 2 0 0 1 0` view save

Test 11

Subtask: 1, 4, 6

Verdict: ACCEPTED

input
`4 2` view save

correct output
`21392 0 1 0 0 510510 804289383 846930886` view save

user output
`999999999 1 0 720 0 0 -1 0` view save

Test 12

Subtask: 1, 4, 6

Verdict: ACCEPTED

input
`4 3` view save

correct output
`1 0 2 0 3 0 804289383 846930886` view save

user output
`999999999 1 0 0 1 0 2 0` view save

Test 13

Subtask: 1, 4, 6

Verdict: ACCEPTED

input
`4 4` view save

correct output
`21392 0 1 0 2 0 0 510510` view save

user output
`0 720 0 0 -1 0 2 0` view save

Test 14

Subtask: 1, 6

Verdict: ACCEPTED

input
`4 5` view save

correct output
`21392 0 22600 0 1 0 0 510510` view save

user output
`0 720 0 0 76 0 2 0` view save

Test 15

Subtask: 1, 2, 6

Verdict: ACCEPTED

input
`4 6` view save

correct output
`1 0 2 0 3 0 4 0` view save

user output
`0 0 1 0 2 0 3 0` view save

Test 16

Subtask: 4, 6

Verdict: ACCEPTED

input
`5 5` view save

correct output
`21392 0 22600 0 1 0 0 510510 804289383 846930886` view save

user output
`999999999 1 0 720 0 0 76 0 2 0` view save

Test 17

Subtask: 4, 6

Verdict: ACCEPTED

input
`6 5` view save

correct output
`21392 0 22600 0 1 0 0 510510 804289383 846930886 ...` view save

user output
`999999999 1 999999998 2 0 720 0 0 76 0 ...` view save

Test 18

Subtask: 3, 4, 5, 6

Verdict: ACCEPTED

input
`98 0` view save

correct output
`1 0 804289383 846930886 681692777 714636915 957747793 424238335 719885386 649760492 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 19

Subtask: 4, 5, 6

Verdict: ACCEPTED

input
`98 97` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 20

Subtask: 4, 5, 6

Verdict: ACCEPTED

input
`98 98` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 21

Subtask: 5, 6

Verdict: ACCEPTED

input
`98 1185` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 22

Subtask: 5, 6

Verdict: ACCEPTED

input
`98 1188` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 23

Subtask: 2, 6

Verdict: ACCEPTED

input
`98 4753` view save

correct output
`1 0 2 0 3 0 4 0 5 0 ...` view save

user output
`0 0 1 0 2 0 3 0 4 0 ...` view save

Test 24

Subtask: 3, 4, 5, 6

Verdict: ACCEPTED

input
`99 0` view save

correct output
`1 0 804289383 846930886 681692777 714636915 957747793 424238335 719885386 649760492 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 25

Subtask: 4, 5, 6

Verdict: ACCEPTED

input
`99 98` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 26

Subtask: 4, 5, 6

Verdict: ACCEPTED

input
`99 99` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 27

Subtask: 5, 6

Verdict: ACCEPTED

input
`99 1201` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 28

Subtask: 5, 6

Verdict: ACCEPTED

input
`99 1212` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 29

Subtask: 2, 6

Verdict: ACCEPTED

input
`99 4851` view save

correct output
`1 0 2 0 3 0 4 0 5 0 ...` view save

user output
`0 0 1 0 2 0 3 0 4 0 ...` view save

Test 30

Subtask: 3, 4, 5, 6

Verdict: ACCEPTED

input
`100 0` view save

correct output
`1 0 804289383 846930886 681692777 714636915 957747793 424238335 719885386 649760492 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 31

Subtask: 4, 5, 6

Verdict: ACCEPTED

input
`100 1` view save

correct output
`1 0 2 0 804289383 846930886 681692777 714636915 957747793 424238335 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 32

Subtask: 4, 5, 6

Verdict: ACCEPTED

input
`100 5` view save

correct output
`21392 0 22600 0 1 0 0 510510 804289383 846930886 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 33

Subtask: 4, 5, 6

Verdict: ACCEPTED

input
`100 100` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 34

Subtask: 5, 6

Verdict: ACCEPTED

input
`100 1000` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 35

Subtask: 5, 6

Verdict: ACCEPTED

input
`100 1232` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 36

Subtask: 5, 6

Verdict: ACCEPTED

input
`100 1237` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 37

Subtask: 6

Verdict: ACCEPTED

input
`100 2222` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 38

Subtask: 6

Verdict: ACCEPTED

input
`100 3395` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`999999999 1 999999998 2 999999997 3 999999996 4 999999995 5 ...` view save

Test 39

Subtask: 2, 6

Verdict: ACCEPTED

input
`100 4950` view save

correct output
`1 0 2 0 3 0 4 0 5 0 ...` view save

user output
`0 0 1 0 2 0 3 0 4 0 ...` view save

Test 40

Subtask: 6

Verdict: ACCEPTED

input
`100 4949` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`0 720 0 0 76 0 -76 0 85 0 ...` view save

Test 41

Subtask: 6

Verdict: ACCEPTED

input
`100 4948` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`0 720 0 0 76 0 -76 0 85 0 ...` view save

Test 42

Subtask: 6

Verdict: ACCEPTED

input
`100 4930` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`0 720 0 0 76 0 -76 0 85 0 ...` view save

Test 43

Subtask: 6

Verdict: ACCEPTED

input
`100 4920` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`0 720 0 0 76 0 -76 0 85 0 ...` view save

Test 44

Subtask: 6

Verdict: ACCEPTED

input
`100 4900` view save

correct output
`21392 0 22600 0 30056 0 34848 0 38584 0 ...` view save

user output
`0 720 0 0 76 0 -76 0 85 0 ...` view save

BOI 2026 Mirror Day 2

Distances

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

Test 16

Test 17

Test 18

Test 19

Test 20

Test 21

Test 22

Test 23

Test 24

Test 25

Test 26

Test 27

Test 28

Test 29

Test 30

Test 31

Test 32

Test 33

Test 34

Test 35

Test 36

Test 37

Test 38

Test 39

Test 40

Test 41

Test 42

Test 43

Test 44

Tasks

Submissions (Sebastian)