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  1. #include <iostream>
  2. #include <vector>
  3. using namespace std;
  4. void solve(){
  5.         int n;
  6.         cin>>n;
  7.         int k;
  8.         cin>>k;
  9.         if (k<n || k == n*2) {
  10.                 cout<<-1<<"\n";
  11.                 return;
  12.         }
  13.         else {
  14.                 vector<vector<int>> grid(n, vector<int>(n, 0));
  15.                 int m=0;
  16.                 int num = 1;
  17.                 //fill diagonal cells
  18.                 while (n*2-k-m!=0){
  19.                         grid[num-1][num-1] = num;
  20.                         m++;
  21.                         num++;
  22.                 }
  23.                 //fill the rest
  24.                 for(int r = 0; r<n; r++){
  25.                         for (int c = 0; c<n; c++){
  26.                                 if (grid[r][c] == 0){
  27.                                         grid[r][c] = num;
  28.                                         num++;
  29.                                 }
  30.                         }
  31.                 }
  32.                 for (int r = 0; r<n; r++){
  33.                         for (int c = 0; c<n;c++){
  34.                                 cout<<grid[r][c]<<" ";
  35.                         }
  36.                         cout<<"\n";
  37.                 }
  38.         }
  39. }
  40. int main(){
  41.         ios_base::sync_with_stdio(false);
  42.         cin.tie(nullptr);
  43.         int t;
  44.         cin>>t;
  45.         while (t--){
  46.                 solve();
  47.         }
  48.         return 0;
  49. }
Success #stdin #stdout 0s 5320KB
comments (?)
stdin
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5
3 0
3 5
5 5
4 3
1 1
stdout
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-1
1 2 3 
4 5 6 
7 8 9 
1 6 7 8 9 
10 2 11 12 13 
14 15 3 16 17 
18 19 20 4 21 
22 23 24 25 5 
-1
1
https://ideone.com/7C4NBP
language:
C++ (gcc 8.3)
created:
1 hour ago
visibility:
public

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