Submission #775097

#	Time	Username	Problem	Language	Result	Execution time	Memory
775097		Polar_Bear_2007	Xor Sort (eJOI20_xorsort)	C++17	25 / 100	94 ms	18552 KiB

xorsort

// #pragma GCC optimize("Ofast,unroll-loops")

#ifdef MINHDEPTRAI
 
#include "/Library/Developer/CommandLineTools/usr/include/c++/v1/bits/stdc++.h"
#include <chrono>
#define __gcd(a, b) gcd(a, b)
using namespace std ::chrono;
#else
#include <bits/stdc++.h>
#endif
using namespace std;
#define foru(i, a, b) for (int i = a; i <= b; ++i)
#define ford(i, a, b) for (int i = a; i >= b; --i)
#define IOS ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define mp(a, b) make_pair(a, b)
// #define int long long
typedef pair<int, int>  pii;
typedef pair<pair<int, int>, int> piii;
#define endl '\n'
const string name_minh = "9";
#define int long long
const int maxN = 2e5 + 5;
const int mod = 1;

const int inf = 1e9;
int n, arr[maxN], k;
map<int, int> counting;
void solve(){
    cin >> n >> k;
    foru(i, 1, n){
        cin >> arr[i];
        counting[arr[i]]++;
    }

    vector<pair<int, int>> ans;
    map<int, int>:: iterator it;
    foru(j, 1, n - 1){

        if(arr[j] > arr[j + 1] && (arr[j] ^ arr[j + 1]) < arr[j + 1]){
            it = counting.find(arr[j] ^ arr[j + 1]); 
            if(it -> second != 0) continue;

            counting[arr[j]]--;
            arr[j] = arr[j] ^ arr[j + 1];
            counting[arr[j]]++;

            ans.push_back(mp(j, j + 1));
        }
    }

    foru(i, 1, n){
        foru(j, 1, n - i){
            if(arr[j] > arr[j + 1]){
                swap(arr[j], arr[j + 1]);
                ans.push_back(mp(j + 1, j));
                ans.push_back(mp(j, j + 1));
                ans.push_back(mp(j + 1, j));
            }
        }
    }
 
    cout << ans.size() << endl;
    for(pair<int, int> x: ans){
        cout << x.first << " " << x.second << endl;
    }
    
}
signed main(){
    IOS
    // #ifdef MINHDEPTRAI 
    // ifstream cin(name_minh + ".in");
    // ofstream cout(name_minh + ".out");
    // #endif
    solve();
   
}

• Subtask 1: 25 / 25
• Subtask 2: 0 / 35
• Subtask 3: 0 / 40