Submission #566037

#	Time	Username	Problem	Language	Result	Execution time	Memory
566037		errorgorn	Xor Sort (eJOI20_xorsort)	C++17	100 / 100	7 ms	1492 KiB

xorsort

// Super Idol的笑容
//    都没你的甜
//  八月正午的阳光
//    都没你耀眼
//  热爱105°C的你
// 滴滴清纯的蒸馏水
 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;
 
#define int long long
#define ll long long
#define ii pair<ll,ll>
#define iii pair<ii,ll>
#define fi first
#define se second
#define endl '\n'
#define debug(x) cout << #x << ": " << x << endl
 
#define pub push_back
#define pob pop_back
#define puf push_front
#define pof pop_front
#define lb lower_bound
#define ub upper_bound
 
#define rep(x,start,end) for(int x=(start)-((start)>(end));x!=(end)-((start)>(end));((start)<(end)?x++:x--))
#define all(x) (x).begin(),(x).end()
#define sz(x) (int)(x).size()
 
#define indexed_set tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>
//change less to less_equal for non distinct pbds, but erase will bug
 
mt19937 rng(chrono::system_clock::now().time_since_epoch().count());
 
int n,k;
int arr[1005];
 
signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin.exceptions(ios::badbit | ios::failbit);
	
	cin>>n>>k;
	rep(x,1,n+1) cin>>arr[x];
	
	vector<ii> ans;
	
	if (k==1){
		rep(x,n+1,1){
			int idx=1;
			rep(y,1,x+1) if (arr[idx]<arr[y]) idx=y;
			
			rep(y,idx,x) swap(arr[y],arr[y+1]);
			
			rep(y,1,min(n,x+1)) ans.pub({y,y+1});
			if (idx-1>=1) rep(y,idx-1,1) ans.pub({y,y+1});
			rep(y,idx,x) ans.pub({y+1,y});
		}
	}
	else{
		int lim=n;
		rep(bit,20,0){
			for (int x=1;x<lim;x++) if (arr[x]&(1<<bit)){
				if ((arr[x+1]&(1<<bit))==0) ans.pub({x+1,x}),arr[x+1]^=arr[x];
				ans.pub({x,x+1}),arr[x]^=arr[x+1];
			}
			if (arr[lim]&(1<<bit)) lim--;
		}
	}
	
	cout<<sz(ans)<<endl;
	for (auto [a,b]:ans) cout<<a<<" "<<b<<endl;
}

• Subtask 1: 25 / 25
• Subtask 2: 35 / 35
• Subtask 3: 40 / 40