Submission #365372

#	Time	Username	Problem	Language	Result	Execution time	Memory
365372		amunduzbaev	Cat (info1cup19_cat)	C++14	0 / 100	23 ms	876 KiB

cat

/** made by amunduzbaev **/
#include <bits/stdc++.h>
using namespace std;
 
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define NeedForSpeed ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define int long long
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii; 
typedef pair<ll, ll> pll; 
typedef vector<ll> vll;
typedef vector<int> vii;
typedef vector<pll> vpll;
typedef vector<pii> vpii;
template<class T> bool umin(T& a, const T& b) {return a > b? a = b, true:false;}
template<class T> bool umax(T& a, const T& b) {return a < b? a = b, true:false;}

const int N = 2e5+5;
const int mod = 1e9+7;
const ll inf = 1e18;
const ld Pi = acos(-1);

#define MULTI 1

int n, m, k, ans, res, a[N], pos[N]; 

/*

1
6
2 6 4 3 1 5

*/

void solve(int t_case){
	//memset(pos, 0, sizeof pos);
	cin>>n;
	for(int i=1;i<=n;i++) cin>>a[i], pos[a[i]] = i;
	//for(int i=1;i<=n;i++) cout<<pos[i]<<" ";
	//cout<<"\n";
	
	//for(int i=1;i<=n;i++) assert(pos[i] != 0);
	
	vpii res;
	for(int i=1;i<=n;i++){
		if(a[i] != i){
			int l = i, r = pos[i];
			assert(l != r);
			res.pb({l, r});
			swap(a[l], a[r]);
			swap(pos[a[l]], pos[a[r]]);
			if(n-l+1 != r){
				l = n-l+1, r = n-r+1;
				assert(l != r);
				swap(a[l], a[r]);
				swap(pos[a[l]], pos[a[r]]);
			}
		}
	}
	for(int i=1;i<=n;i++){
		if(a[i] != i){
			cout<<-1<<"\n";
			return;
		}
	}
	
	cout<<sz(res)<<" "<<0<<"\n";
	for(auto x:res) cout<<x.ff<<" "<<x.ss<<"\n";
}

signed main(){
	NeedForSpeed
	
	if(!MULTI) {
		solve(1);
	} else {
		int t; cin>>t;
		for(int t_case = 1; t_case <= t; t_case++) solve(t_case);
	}
	return 0;
}

• Subtask 1: 0 / 15
• Subtask 2: 0 / 10
• Subtask 3: 0 / 25
• Subtask 4: 0 / 15
• Subtask 5: 0 / 35