Submission #988306

#	Time	Username	Problem	Language	Result	Execution time	Memory
988306		mariza	Xor Sort (eJOI20_xorsort)	C++14	0 / 100	1 ms	348 KiB

xorsort

#include <bits/stdc++.h>
using namespace std;

//i/o optimizations
#define fastio ios::sync_with_stdio(0);cin.tie(0);cout.tie(0)

//data types & structures
typedef long long ll;
typedef unsigned long long ull;
typedef __int128 lll;
#define pq priority_queue

//graph structures
typedef vector<pair<ll,ll>> graph;
typedef vector<ll> nw_graph;
typedef vector<ll> tree;
typedef pair<ll,pair<ll,ll>> edge;
typedef pq<pair<ll,ll>> dij_q;

//constant values
const ll N=2e5+1;
const ll N3=1e3+1;
const ll N4=1e4+1;
const ll N5=1e5+1;
const ll N6=1e6+1;
const ll N8=1e8+1;
const ll INF=1e18+1;
const ll LOGN=18;
const ll MOD=1e9+7;
const ll MOD2=998244353;

//operations
#define MID ((l+r)/2)
#define RANGE (r-l+1)
#define CEIL(a,b) (((a)/(b))+(((a)%(b))?1:0))

//output
#define YES cout<<"YES"<<endl
#define NO cout<<"NO"<<endl
#define ANS(ans) if(ans) YES; else NO

//math
ll mpow(ll b, ll p, ll m=MOD){ll ans=1; while(p>0){ if(p%2==1)ans*=b; b=(b*b)%MOD; p/=2; ans%=MOD;} return ans;}

int main(){
    fastio;

    ll n, s;
    cin>>n>>s;
    ll a[n];
    for(ll i=0; i<n; i++){
        cin>>a[i];
    }
    
    vector<pair<ll,ll>> x;
    for(ll i=0; i<n; i++){
        ll k=i;
        for(ll j=i; j<n; j++){
            if(a[j]<a[k]) k=j;
        }
        
        if(k!=i) x.push_back({i,k});
        swap(a[i],a[k]);
    }
    
    cout<<3*x.size()<<endl;
    for(auto i:x){
        cout<<i.first+1<<" "<<i.second+1<<endl;
        cout<<i.second+1<<" "<<i.first+1<<endl;
        cout<<i.first+1<<" "<<i.second+1<<endl;
    }

    return 0;
}

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