Submission #210990

#	Time	Username	Problem	Language	Result	Execution time	Memory
210990		ryansee	DEL13 (info1cup18_del13)	C++14	40 / 100	34 ms	1556 KiB

del13

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

#define FAST ios_base::sync_with_stdio(false); cin.tie(0);
#define pb push_back
#define eb emplace_back
#define ins insert
#define ph push
#define f first
#define s second
#define cbr cerr << "hi\n"
#define mmst(x, v) memset((x), v, sizeof ((x)))
#define siz(x) ll(x.size())
#define all(x) (x).begin(), (x).end()
#define lbd(x, y) lower_bound(all(x), y)
#define ubd(x, y) upper_bound(all(x), y)
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());    //can be used by calling rng() or shuffle(A, A+n, rng)
inline long long rand(long long x, long long y) { return (rng() % (y+1-x)) + x; } //inclusivesss
string inline to_string(char c) {string s(1,c);return s;} template<typename T> inline T gcd(T a,T b){ return a==0?llabs(b):gcd(b%a,a); }

typedef long long ll; 
typedef long double ld;
#define FOR(i,s,e) for(ll i=s;i<=ll(e);++i)
#define DEC(i,s,e) for(ll i=s;i>=ll(e);--i)
typedef pair<ll,ll>pi; typedef pair<ll,pi>spi; typedef pair<pi,pi>dpi;

#define LLINF ((long long)1e18)
#define INF int(1e9+1e6)
#define MAXN (300006)
bool state[MAXN];
void solve(){
	mmst(state,0);
	ll n,q;cin>>n>>q;
	FOR(i,0,q-1){
		ll a; cin>>a;
		state[a]=1;
	}
	vector<ll> comp;
	vector<vector<bool>> dp(2,vector<bool>(n+4,0));
	vector<ll> moves, ans, re;
	auto gogo=[&](){
		if(comp.empty())return 1;
		vector<vector<ll>> came(siz(comp), vector<ll>());
		FOR(i,0,siz(comp)-1){
			came[i].resize(comp[i]+3);
			FOR(j,0,comp[i]+2) dp[i&1][j]=0, came[i][j]=-1;
			if(i) for(ll j=1;j<=min(comp[i-1],comp[i]);++j) if(dp[(i-1)&1][j]) {
				dp[i&1][comp[i]-j]=1, came[i][comp[i]-j]=j;
			}
			if(comp[i]>2){
				DEC(j,comp[i]-1,0){
					if(dp[i&1][j+2]&&!dp[i&1][j]){
						came[i][j]=came[i][j+2];
					}
					dp[i&1][j]=dp[i&1][j]|dp[i&1][j+2];
				}
			}
			if(i==0||dp[(i-1)&1][0]){
				dp[i&1][comp[i]]=1, came[i][comp[i]]=0;
				DEC(j,comp[i]-1,1){
					if(dp[i&1][j+2]&&!dp[i&1][j]){
						came[i][j]=came[i][j+2];
					}
					dp[i&1][j]=dp[i&1][j]|dp[i&1][j+2];
				}
			}
		}
		if(dp[(siz(comp)-1)&1][0]){
			ll x=siz(comp)-1, y=0;
			assert(moves.empty());
			moves.pb(0);
			while(x){
				assert(~came[x][y]), moves.pb(came[x][y]), y=came[x][y], -- x;
			}
			reverse(all(moves));
			assert(moves.size()==comp.size());
			re.clear(), re.resize(moves.size(),0);
			FOR(i,0,siz(moves)-1){
				if(i==0) {
					re[i]=moves[i], moves[i]=comp[i]-moves[i];
				}else{
					re[i]=moves[i], moves[i]=comp[i]-re[i-1]-moves[i];
				}
			}
			return 1;
		}
		cout<<"-1\n";
		return 0;
	};
	ll past=0;
	auto get_move=[&](){
		assert(moves.size()==comp.size());
		ll opast=past;
		FOR(i,0,siz(comp)-1){
			ll to_bye=moves[i];
			assert(to_bye%2==0);
			to_bye/=2;
			assert(comp[i]-to_bye*2>=1); assert(comp[i]-to_bye*2-(i?re[i-1]:0)==re[i]);
			while(to_bye--){
				ans.pb(past+2);assert(state[past+2]==0);
			}
			past += comp[i] + 1;
		}
		past=opast;
		FOR(i,0,siz(comp)-1){
			past+=comp[i]+1;
			moves[i]=re[i];
			if(siz(comp)-1==i)assert(moves[i]==0);
			while(moves[i]--)assert(state[past]==1),ans.pb(past);
		}
	};
	FOR(i,1,n){
		if(state[i]==0){
			if(i>1&&state[i-1]==0) {
				++ comp.back();
			}else{
				comp.pb(1);
			}
		}else{
			if(i>1&&state[i-1]==1){
				if(!gogo())return;
				get_move();
				comp.clear();
				moves.clear(), re.clear();
				++ past;
			}else { past+=(i==1); assert(i==1||comp.size()); }
		}
	}
	if(!gogo())return;
	get_move();
	if(state[n]==0)assert(past==n+1);
	else assert(past==n);
	cout<<ans.size()<<'\n';
	for(auto i:ans)assert(i>1&&i<n),cout<<i<<' ';cout<<'\n';
}
int main(){
	FAST
	ll t; cin>>t;
	while(t--)solve();
}

• Subtask 1: 6 / 15
• Subtask 2: 6 / 15
• Subtask 3: 6 / 15
• Subtask 4: 10 / 25
• Subtask 5: 12 / 30