Submission #456368

#	Time	Username	Problem	Language	Result	Execution time	Memory
456368		dxz05	Longest beautiful sequence (IZhO17_subsequence)	C++14	40 / 100	54 ms	3792 KiB

subsequence

#pragma GCC optimize("Ofast,O2,O3")
#pragma GCC target("avx2")

#include <bits/stdc++.h>

using namespace std;

void debug_out() { cerr << endl; }

template<typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
    cerr << "[" << H << "]";
    debug_out(T...);
}

#ifdef dddxxz
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

#define SZ(s) ((int)s.size())
#define all(x) (x).begin(), (x).end()
#define revall(x) (x).rbegin(), (x).rend()

clock_t startTime;

double getCurrentTime() {
    return (double) (clock() - startTime) / CLOCKS_PER_SEC;
}

#define MP make_pair

typedef long long ll;
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
const double eps = 0.00001;
const int MOD = 1e9;
const int INF = 1000000101;
const long long LLINF = 1223372000000000555;
const int N = 2e6 + 3e2;
const int M = 5055;

#define blp(x) __builtin_popcount(x)

int n;
int a[N], b[N];

bool can(int i, int j){
    if (i > j) swap(i, j);
    return (blp(a[i] & a[j]) == b[j]);
}

void Subtask_2(){
    vector<int> dp(n + 1);
    for (int i = 1; i <= n; i++){
        dp[i] = 1;
        for (int j = 1; j < i; j++){
            if (blp(a[j] & a[i]) == b[i]) dp[i] = max(dp[i], dp[j] + 1);
        }
    }

    int i = max_element(all(dp)) - dp.begin();

    vector<int> ans;
    while (i > 0){
        ans.push_back(i);
        int j = i;
        while (j >= 1 && (!can(i, j) || dp[i] != dp[j] + 1)) j--;
        i = j;
    }

    reverse(ans.begin(), ans.end());

    cout << ans.size() << endl;
    for (int x : ans) cout << x << ' ';
    cout << endl;

    exit(0);
}

void Subtask_3(){
    vector<int> dp(n + 1);
    vector<int> dp2(256);
    for (int i = 1; i <= n; i++){
        dp[i] = 1;
        for (int x = 0; x < 256; x++){
            if (blp(x & a[i]) == b[i]) dp[i] = max(dp[i], dp2[x] + 1);
        }
        dp2[a[i]] = max(dp2[a[i]], dp[i]);
    }

    int i = max_element(all(dp)) - dp.begin();

    vector<int> ans;
    while (i > 0){
        ans.push_back(i);
        int j = i;
        while (j >= 1 && (!can(i, j) || dp[i] != dp[j] + 1)) j--;
        i = j;
    }

    reverse(ans.begin(), ans.end());

    cout << ans.size() << endl;
    for (int x : ans) cout << x << ' ';
    cout << endl;

    exit(0);
}

void solve(int TC) {
    cin >> n;

    for (int i = 1; i <= n; i++) cin >> a[i];
    for (int i = 1; i <= n; i++) cin >> b[i];

    if (n <= 5000) Subtask_2();
    Subtask_3();
    
}

int main() {
    startTime = clock();
    cin.tie(nullptr);
    cout.tie(nullptr);
    ios_base::sync_with_stdio(false);

    bool llololcal = false;
#ifdef dddxxz
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    llololcal = true;
#endif

    int TC = 1;
    //cin >> TC;

    for (int test = 1; test <= TC; test++) {
        debug(test);
        //cout << "Case #" << test << ": ";
        solve(test);
    }

    if (llololcal) cerr << endl << "Time: " << int(getCurrentTime() * 1000) << " ms" << endl;

    return 0;
}

Compilation message (stderr)

subsequence.cpp: In function 'int main()':
subsequence.cpp:19:20: warning: statement has no effect [-Wunused-value]
   19 | #define debug(...) 42
      |                    ^~
subsequence.cpp:139:9: note: in expansion of macro 'debug'
  139 |         debug(test);
      |         ^~~~~

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