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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3. typedef long long ll;
  4. const int Mod=998244353;
  5.  
  6. void solve() {
  7.        int n;
  8.        cin >> n;
  9.        vector<int> a(n);
  10.        for(int i=0;i<n;i++) cin >> a[i];
  11.        if(n==2){
  12.         cout << 2 << '\n';
  13.         cout << 1 << " " << 1 << '\n';
  14.         cout << 2 << " " << 2 << '\n';
  15.         return;
  16.        }
  17.        if(n%2==0){
  18.         cout << 4 << '\n';
  19.         cout << 1 << " " << 1 << '\n';
  20.         cout << n << " " << n << '\n';
  21.         cout << 2 << " " << n-1 << '\n';
  22.         cout << 1 << " " << n << '\n';
  23.         return;
  24.        }
  25.        else{
  26.         cout << 3 << '\n';
  27.         cout << 1 << " " << 1 << '\n';
  28.         cout << 2 << " " << n << '\n';
  29.         cout << 1 << " " << n << '\n';
  30.         return;
  31.        }
  32. }
  33.  
  34. int main(){ 
  35.     ios::sync_with_stdio(false);
  36.     cin.tie(nullptr);
  37.  
  38.     int t;
  39.     cin >> t;
  40.     while (t--) solve();
  41.  
  42.  
  43.     return 0;
  44. }
  45.  
Success #stdin #stdout 0.01s 5324KB
comments (?)
stdin
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6
4
1 2 3 0
8
3 1 4 1 5 9 2 6
6
1 5 4 1 4 7
5
0 0 0 0 0
7
1 1 9 9 0 1 8
3
100 100 0
stdout
copy 
4
1 1
4 4
2 3
1 4
4
1 1
8 8
2 7
1 8
4
1 1
6 6
2 5
1 6
3
1 1
2 5
1 5
3
1 1
2 7
1 7
3
1 1
2 3
1 3
https://ideone.com/wvgP24
language:
C++ (gcc 8.3)
created:
1 day ago
visibility:
public

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