Submission #1134865

#	Time	Username	Problem	Language	Result	Execution time	Memory
1134865		steveonalex	Beautiful row (IZhO12_beauty)	C++20	100 / 100	327 ms	164600 KiB

beauty

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;

#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
#define ALL(v) (v).begin(), (v).end()

ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}

ll gcd(ll a, ll b){return __gcd(a, b);}
ll LASTBIT(ll mask){return (mask) & (-mask);}
int pop_cnt(ll mask){return __builtin_popcountll(mask);}
int ctz(ll mask){return __builtin_ctzll(mask);}
int logOf(ll mask){return __lg(mask);}

mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);}

template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b) {a = b; return true;}
        return false;
    }

template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b) {a = b; return true;}
        return false;
    }

template <class T>
    void printArr(T& container, string separator = " ", string finish = "\n"){
        for(auto item: container) cout << item << separator;
        cout << finish;
    }


template <class T>
    void remove_dup(vector<T> &a){
        sort(ALL(a));
        a.resize(unique(ALL(a)) - a.begin());
    }

const int N = 20;
bool graph[N][N];
ll dp[MASK(N)][N];

void solve(){
    int n; cin >> n;
    vector<int> a(n);
    for(int i = 0; i< n; ++i) cin >> a[i];

    for(int i= 0; i < n; ++i) for(int j = 0; j < n; ++j){
        if (pop_cnt(a[i]) == pop_cnt(a[j])) graph[i][j] = 1;
        else{
            int x = a[i], y = a[j];
            int cnt = 0;
            while(x > 0 || y > 0){
                cnt += (x % 3 == 1) - (y % 3 == 1);
                x /= 3; y /= 3;
            }
            if (cnt == 0) graph[i][j] = 1;
        }
    }
    for(int i = 0; i< n; ++i) dp[MASK(i)][i] = 1;
    for(int mask = 1; mask < MASK(n) - 1; ++mask){
        for(int dcm = mask; dcm > 0; dcm -= LASTBIT(dcm)){
            int i = ctz(dcm);
            if (dp[mask][i] == 0) continue;
            for(int vcl = MASK(n) - 1 - mask; vcl > 0; vcl -= LASTBIT(vcl)){
                int j = ctz(vcl);
                if (graph[i][j]) dp[mask + MASK(j)][j] += dp[mask][i];
            }
        }
    }

    ll ans = 0;
    for(int i = 0; i < n; ++i) ans += dp[MASK(n) - 1][i];

    cout << ans << "\n";
}

int main(void){
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    clock_t start = clock();

    solve();

    cerr << "Time elapsed: " << clock() - start << "ms!\n";
    return 0;
}

• Subtask 1: 100 / 100