CSES - BOI 2026 Mirror Day 2

Submission details
Task:	Distances
Sender:	Diego_09
Submission time:	2026-04-17 13:14:35 +0300
Language:	C++ (C++17)
Status:	READY
Result:	21

Feedback
subtask	verdict	score
#1	ACCEPTED	11
#2	ACCEPTED	4
#3	ACCEPTED	6
#4	RUNTIME ERROR	0
#5	RUNTIME ERROR	0
#6	RUNTIME ERROR	0

Test results
test	verdict	time	subtask
#1	ACCEPTED	0.49 s	1, 4, 6	details
#2	ACCEPTED	0.40 s	1, 2, 3, 4, 5, 6	details
#3	ACCEPTED	0.40 s	1, 3, 4, 5, 6	details
#4	ACCEPTED	0.40 s	1, 2, 4, 6	details
#5	ACCEPTED	0.39 s	1, 3, 4, 5, 6	details
#6	ACCEPTED	0.39 s	1, 4, 6	details
#7	ACCEPTED	0.40 s	1, 4, 6	details
#8	ACCEPTED	0.53 s	1, 2, 4, 6	details
#9	ACCEPTED	0.39 s	1, 3, 4, 5, 6	details
#10	ACCEPTED	0.41 s	1, 4, 5, 6	details
#11	ACCEPTED	0.39 s	1, 4, 6	details
#12	ACCEPTED	0.39 s	1, 4, 6	details
#13	ACCEPTED	0.50 s	1, 4, 6	details
#14	ACCEPTED	0.39 s	1, 6	details
#15	ACCEPTED	0.39 s	1, 2, 6	details
#16	ACCEPTED	0.40 s	4, 6	details
#17	ACCEPTED	0.39 s	4, 6	details
#18	ACCEPTED	0.39 s	3, 4, 5, 6	details
#19	RUNTIME ERROR	0.40 s	4, 5, 6	details
#20	WRONG ANSWER	0.40 s	4, 5, 6	details
#21	WRONG ANSWER	0.40 s	5, 6	details
#22	WRONG ANSWER	0.39 s	5, 6	details
#23	ACCEPTED	0.40 s	2, 6	details
#24	ACCEPTED	0.40 s	3, 4, 5, 6	details
#25	RUNTIME ERROR	0.40 s	4, 5, 6	details
#26	WRONG ANSWER	0.40 s	4, 5, 6	details
#27	WRONG ANSWER	0.40 s	5, 6	details
#28	WRONG ANSWER	0.40 s	5, 6	details
#29	ACCEPTED	0.39 s	2, 6	details
#30	ACCEPTED	0.39 s	3, 4, 5, 6	details
#31	ACCEPTED	0.40 s	4, 5, 6	details
#32	ACCEPTED	0.40 s	4, 5, 6	details
#33	WRONG ANSWER	0.51 s	4, 5, 6	details
#34	WRONG ANSWER	0.40 s	5, 6	details
#35	WRONG ANSWER	0.40 s	5, 6	details
#36	WRONG ANSWER	0.40 s	5, 6	details
#37	WRONG ANSWER	0.39 s	6	details
#38	WRONG ANSWER	0.40 s	6	details
#39	ACCEPTED	0.41 s	2, 6	details
#40	WRONG ANSWER	0.39 s	6	details
#41	WRONG ANSWER	0.39 s	6	details
#42	WRONG ANSWER	0.49 s	6	details
#43	WRONG ANSWER	0.40 s	6	details
#44	WRONG ANSWER	0.39 s	6	details

Compiler report

input/code.cpp: In function 'void solve()':
input/code.cpp:124:26: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  124 |             for(int i=0;i<p.size();i++){
      |                         ~^~~~~~~~~
input/code.cpp:127:32: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  127 |                 for(int j=i+1;j<p.size();j++){
      |                               ~^~~~~~~~~

Code

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#if defined(__has_include)&&__has_include("custom_h/debugging.h")
#define local_run 1
#include "custom_h\debugging.h"
#else 
#define local_run 0
#endif
// #pragma GCC target ("avx2");
// #pragma GCC optimize ("Ofast");
#define rall(v) v.rbegin(),v.rend()
#define all(v) v.begin(),v.end()
#define keyval find_by_order
#define valkey order_of_key
#define int long long
#define pb push_back
#define s second
#define f first

using namespace __gnu_pbds; 
using namespace std;
template<typename T>
using oset=tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
template<typename T>
using omset=tree<T,null_type,less_equal<T>,rb_tree_tag,tree_order_statistics_node_update>;
    
void set_io(string name=""){
    ios_base::sync_with_stdio(0);cin.tie(0);
    if(name.size() and !local_run){
        // freopen((name+".in").c_str(),"r",stdin);
        // freopen((name+".out").c_str(),"w",stdout);
    }
}

const int my[]={0,0,1,-1,1,1,-1,-1};
const int mx[]={1,-1,0,0,1,-1,-1,1};
const int md=1e9+7;
const int oo=1e18;

map<int,bool>sq;

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

    for(int i=0;i<=1000000;i++){
        sq[i*i]=1;
    }

    if(k*2==n*(n-1)){
        for(int i=1;i<=n;i++)cout<<"1 "<<i<<"\n";
        return;
    }
    if(k==0){       
        for(int i=1;i<=n;i++)cout<<i<<" "<<i<<"\n";
        return;
    }

    if(n==1){
        cout<<"1 1\n";
        return;
    }if(n==2){
        cout<<"1 1\n2 2\n";
        return;
    }if(n==3){
        if(k==1)cout<<"1 1\n1 2\n2 3\n";
        else cout<<"1 1\n1 2\n2 2\n";
        return;
    }if(n==4){
        if(k==1)cout<<"1 1\n1 2\n2 3\n3 4\n";
        else if(k==2)cout<<"1 1\n1 2\n2 2\n3 3\n";
        else if(k==3)cout<<"1 1\n1 2\n1 3\n2 4\n";
        else if(k==4)cout<<"1 1\n1 2\n1 3\n2 3\n";
        else cout<<"1 1\n1 4\n5 4\n9 7\n";
        return;
    }

    if(k<=n){
        if(k==n){
            vector<pair<int,int>>p={{1,1},{1,2},{1,3}};
            int x=2,y=3;
            for(int i=3;i<k;i++){
                p.pb({x,y});
                if(i%2)y++;
                else x++;
            }
            for(auto cc:p)cout<<cc.f<<" "<<cc.s<<"\n";
        }else{
            vector<pair<int,int>>p;

            int x=0,y=1;
            for(int i=0;i<=k;i++){
                if(i%2)y++;
                else x++;
                p.pb({x,y});
            }         

            x=-100000000;
            y=100000000;

            for(int i=1;i<n-k;i++){
                bool ok=1;

                while(1){
                    x++;
                    y--;

                    ok=1;
                    for(auto cc:p){
                        if(sq[pow(abs(x-cc.f),2)+pow(abs(y-cc.s),2)]==1 or cc.f==x or cc.s==y){
                            ok=0;
                            break;
                        }
                    }

                    if(ok==1)break;
                }

                p.pb({x,y});
            }

            int cont=0;
            for(int i=0;i<p.size();i++){
                int x1=p[i].f;
                int y1=p[i].s;
                for(int j=i+1;j<p.size();j++){
                    int a1=p[j].f;
                    int b1=p[j].s;
                    if(sq[pow(abs(x1-a1),2)+pow(abs(y1-b1),2)]==1 or x1==a1 or y1==b1){
                        cont++;
                    }
                }
            }

            if(cont!=k)exit(-1);
            
            for(auto cc:p)cout<<cc.f<<" "<<cc.s<<"\n";
        }
    }
}

int32_t main(){set_io("");
    int t=1;
    // cin>>t;
    while(t--){
        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
`1 1 1 2 2 2` 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
`1 1` 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
`1 1 2 2` 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
`1 1 1 2` 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
`1 1 2 2 3 3` 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
`1 1 1 2 2 3` 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
`1 1 1 2 2 2` 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
`1 1 1 2 1 3` 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
`1 1 2 2 3 3 4 4` 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
`1 1 1 2 2 3 3 4` 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
`1 1 1 2 2 2 3 3` 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
`1 1 1 2 1 3 2 4` 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
`1 1 1 2 1 3 2 3` 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
`1 1 1 4 5 4 9 7` 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
`1 1 1 2 1 3 1 4` 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
`1 1 1 2 1 3 2 3 2 4` 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
`1 1 1 2 2 2 2 3 3 3 ...` 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
`1 1 2 2 3 3 4 4 5 5 ...` view save

Test 19

Subtask: 4, 5, 6

Verdict: RUNTIME ERROR

input
`98 97` view save

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

user output
(empty)

Test 20

Subtask: 4, 5, 6

Verdict: WRONG ANSWER

input
`98 98` view save

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

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

Test 21

Subtask: 5, 6

Verdict: WRONG ANSWER

input
`98 1185` view save

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

user output
(empty)

Test 22

Subtask: 5, 6

Verdict: WRONG ANSWER

input
`98 1188` view save

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

user output
(empty)

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
`1 1 1 2 1 3 1 4 1 5 ...` 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
`1 1 2 2 3 3 4 4 5 5 ...` view save

Test 25

Subtask: 4, 5, 6

Verdict: RUNTIME ERROR

input
`99 98` view save

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

user output
(empty)

Test 26

Subtask: 4, 5, 6

Verdict: WRONG ANSWER

input
`99 99` view save

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

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

Test 27

Subtask: 5, 6

Verdict: WRONG ANSWER

input
`99 1201` view save

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

user output
(empty)

Test 28

Subtask: 5, 6

Verdict: WRONG ANSWER

input
`99 1212` view save

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

user output
(empty)

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
`1 1 1 2 1 3 1 4 1 5 ...` 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
`1 1 2 2 3 3 4 4 5 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
`1 1 1 2 -99999999 99999999 -99999998 99999998 -99999997 99999997 ...` 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
`1 1 1 2 2 2 2 3 3 3 ...` view save

Test 33

Subtask: 4, 5, 6

Verdict: WRONG ANSWER

input
`100 100` view save

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

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

Test 34

Subtask: 5, 6

Verdict: WRONG ANSWER

input
`100 1000` view save

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

user output
(empty)

Test 35

Subtask: 5, 6

Verdict: WRONG ANSWER

input
`100 1232` view save

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

user output
(empty)

Test 36

Subtask: 5, 6

Verdict: WRONG ANSWER

input
`100 1237` view save

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

user output
(empty)

Test 37

Subtask: 6

Verdict: WRONG ANSWER

input
`100 2222` view save

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

user output
(empty)

Test 38

Subtask: 6

Verdict: WRONG ANSWER

input
`100 3395` view save

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

user output
(empty)

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
`1 1 1 2 1 3 1 4 1 5 ...` view save

Test 40

Subtask: 6

Verdict: WRONG ANSWER

input
`100 4949` view save

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

user output
(empty)

Test 41

Subtask: 6

Verdict: WRONG ANSWER

input
`100 4948` view save

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

user output
(empty)

Test 42

Subtask: 6

Verdict: WRONG ANSWER

input
`100 4930` view save

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

user output
(empty)

Test 43

Subtask: 6

Verdict: WRONG ANSWER

input
`100 4920` view save

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

user output
(empty)

Test 44

Subtask: 6

Verdict: WRONG ANSWER

input
`100 4900` view save

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

user output
(empty)

BOI 2026 Mirror Day 2

Distances

Compiler report

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 (Diego_09)