Submission #59355

#	Time	Username	Problem	Language	Result	Execution time	Memory
59355		Benq	medians (balkan11_medians)	C++14	100 / 100	46 ms	3088 KiB

medians

#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 200001;

int n;
bool use[MX];
int l, r;
vi ans;

int getFst() {
    while (use[l]) l++;
    use[l] = 1;
    return l;
}

int getLst() {
    while (use[r]) r--;
    use[r] = 1;
    return r;
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n; l = 1, r = 2*n-1;
    int lst; cin >> lst; ans.pb(lst); use[lst] = 1;
    F0R(i,n-1) {
        int x; cin >> x;
        if (x == lst) {
            ans.pb(getFst());
            ans.pb(getLst());
        } else if (x < lst) {
            if (use[x]) {
                ans.pb(getFst());
                ans.pb(getFst());
            } else {
                use[x] = 1;
                ans.pb(x);
                ans.pb(getFst());
            }
        } else {
            if (use[x]) {
                ans.pb(getLst());
                ans.pb(getLst());
            } else {
                use[x] = 1;
                ans.pb(x);
                ans.pb(getLst());
            }
        }
        lst = x;
    }
    for (int i: ans) cout << i << " ";
}

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/

• Subtask 1: 65 / 65
• Subtask 2: 35 / 35