Submission #58056

#	Time	Username	Problem	Language	Result	Execution time	Memory
58056		Benq	Norela (info1cup18_norela)	C++14	100 / 100	95 ms	1020 KiB

norela

#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 = 100001;

int n,m;
ll cur[24], des, ans;

ll bet(ll a, ll b) {
    if (__builtin_popcount(a) < __builtin_popcount(b)) return a;
    if (__builtin_popcount(a) > __builtin_popcount(b)) return b;
    F0R(i,m) {
        ll x = a&(1LL<<i);
        ll y = b&(1LL<<i);
        if (x < y) return b;
        if (x > y) return a;
    }
    return a;
}

void search(int ind, ll c, ll use) {
    if (c == des) {
        ans = bet(ans,use);
        return;
    }
    if (ind == m) return;
    search(ind+1,c^cur[ind],use^(1LL<<ind));
    search(ind+1,c,use);
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> m;
    des = (1LL<<n)-1; 
    ans = (1LL<<m)-1;
    F0R(i,m) {
        int x; cin >> x;
        F0R(j,x) {
            int t; cin >> t; t --;
            cur[i] ^= 1LL<<t;
        }
    }
    search(0,0,0);
    cout << __builtin_popcount(ans) << "\n";
    F0R(i,m) if (ans&(1LL<<i)) cout << i+1 << " ";
}

/* 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: 20 / 20
• Subtask 2: 30 / 30
• Subtask 3: 25 / 25
• Subtask 4: 25 / 25