Submission #1209188

#	Time	Username	Problem	Language	Result	Execution time	Memory
1209188		M_SH_O	DEL13 (info1cup18_del13)	C++20	15 / 100	3 ms	1196 KiB

del13

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

#define ll long long
#define ll1 long long
#define ull unsigned long long
#define dou long double
#define str string
#define vll vector<ll>
#define vi vector<int>
#define pll pair<ll, ll>
#define vpll vector<pll>
#define vbool vector<bool>
#define vstr vector<str>
#define vvll vector<vll>
#define pb push_back
#define pf push_front
#define endl "\n"
#define fr first
#define se second
// #define sortcmp(a) sort(a.begin(), a.end(), cmp)
#define sort(a) sort(a.begin(), a.end())
#define reverse(a) reverse(a.begin(), a.end())
#define speed ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define INF 5000000000000000000
#define ordered_set tree<ll, null_type, less_equal<ll>, rb_tree_tag, tree_order_statistics_node_update>

using namespace std;
//using namespace __gnu_pbds;

mt19937 rng(1488);
ll randll(ll l, ll r){
    return uniform_int_distribution<ll>(l, r)(rng);
}

int main() {
    speed;
    srand(time(0));

    ll t;
    cin >> t;

    while (t --) {
        ll n, k;
        cin >> n >> k;
        vll a;
        a.pb(0);
        for (int i = 0; i < k; i ++) {
            ll b;
            cin >> b;
            a.pb(b);
        }
        a.pb(n+1);
        k = 0;
        bool q = 1;
        vll res;

        for (int i = 1; i < a.size(); i ++) {
            ll s = a[i]-a[i-1]-1;
            for (int j = 0; j < s/2+s%2-1; j ++) {
                res.pb((a[i]+a[i-1])/2);
            }
            if (s == 0) {
                if (k > 0) {
                    q = 0;
                    break;
                }
                continue;
            }
            s %= 2;
            if (s == 0) s = 2;
            if (k == 0) {
                k = s;
            }
            else if (k == 1) {
                res.pb(a[i-1]);
                k = s-1;
            }
            else {
                if (s == 1) {
                    q = 0;
                    break;
                }
                res.pb(a[i-1]);
                res.pb(a[i-1]);
                k = 0;
            }
        }

        if (q && k == 0) {
            cout << res.size() << endl;
            for (int i : res) {
                cout << i << ' ';
            }
            cout << endl;
        }
        else cout << -1 << endl;
    }


}

• Subtask 1: 0 / 15
• Subtask 2: 0 / 15
• Subtask 3: 15 / 15
• Subtask 4: 0 / 25
• Subtask 5: 0 / 30