Submission #334739

#	Time	Username	Problem	Language	Result	Execution time	Memory
334739		limabeans	Longest beautiful sequence (IZhO17_subsequence)	C++17	40 / 100	6026 ms	3020 KiB

subsequence

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

template<typename T>
void out(T x) { cout << x << endl; exit(0); }
#define watch(x) cout << (#x) << " is " << (x) << endl





using ll = long long;


const int maxn = 1e6 + 5;



int n;
int a[maxn];
int k[maxn];

int dp[maxn], p[maxn];


bool compat(int i, int j) {
    return __builtin_popcount(a[i]&a[j]) == k[j];
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0);  cout.tie(0);

    cin>>n;
    bool task3 = true;
    for (int i=0; i<n; i++) {
	cin>>a[i];
	task3 &= (a[i]<256);
    }
    for (int i=0; i<n; i++) {
	cin>>k[i];
    }


    if (task3) {
	//watch(task3);
	vector<pair<int,int>> w(256, {-1,-1}); //dp[i],i
	for (int i=0; i<n; i++) {
	    dp[i]=1;
	    p[i]=-1;
	    for (int x=0; x<256; x++) {
		if (k[i]==__builtin_popcount(x&a[i])) {
		    if (w[x].first+1>dp[i]) {
			dp[i]=w[x].first+1;
			p[i]=w[x].second;
		    }
		}
	    }
	    w[a[i]]=max(w[a[i]],{dp[i],i});
	}
    } else {
	for (int i=0; i<n; i++) {
	    dp[i]=1;
	    p[i]=-1;
	    for (int j=i-1; j>=0; j--) {
		if (compat(j,i) && 1+dp[j]>dp[i]) {
		    dp[i]=1+dp[j];
		    p[i]=j;
		}
	    }
	}
    }

    int at=n-1;
    for (int i=0; i<n; i++) {
	if (dp[i]>dp[at]) at=i;
    }

    vector<int> ans;
    while (~at) {
	ans.push_back(at);
	at=p[at];
    }

    sort(ans.begin(),ans.end());
    cout<<ans.size()<<"\n";
    for (int i: ans) cout<<i+1<<" ";
    cout<<endl;

    
    return 0;
}

• Subtask 1: 7 / 7
• Subtask 2: 16 / 16
• Subtask 3: 17 / 17
• Subtask 4: 0 / 60