Submission #403606

#	Time	Username	Problem	Language	Result	Execution time	Memory
403606		lyc	족보 (KOI18_family)	C++14	59 / 100	600 ms	196940 KiB

family

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

#define TRACE(x) cerr << #x << " :: " << x << endl
#define _ << " " <<
#define SZ(x) (int)(x).size()
#define ALL(x) (x).begin(),(x).end()
#define FOR(i,a,b) for(int i=(a);i<=(b);++i)
#define RFOR(i,a,b) for (int i=(a);i>=(b);--i)

//const int mxN = 3e5+5;
//const int mxK = 3e5+5;
const int mxN = 5005;
const int mxK = 5005;
const int inf = 1e9+5;

int K;

struct Tree {
    int N;
    vector<int> g[mxN];
    int pa[mxN];
    int dep[mxN];
    int _lca[mxK][mxK];

    void read() {
        FOR(i,1,N){
            int P; cin >> P;
            g[P].push_back(i);
        }
    }

    void dfs(int u) {
        for (int& v : g[u]) {
            pa[v] = u;
            dep[v] = dep[u]+1;
            dfs(v);
        }
    }

    int lca(int a, int b) {
        if (_lca[a][b] != -1) return _lca[a][b];
        if (a == b) return a;
        if (dep[a] > dep[b]) {
            return _lca[a][b] = lca(pa[a],b);
        } else {
            return _lca[a][b] = lca(a,pa[b]);
        }
    }

    void run() {
        memset(pa,-1,sizeof pa);
        dep[0] = 0;
        dfs(0);
        memset(_lca,-1,sizeof _lca);
    }

    inline int lcd(int a, int b) {
        return dep[lca(a,b)];
    }
} A, B;

int mn[mxN];

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

    cin >> A.N >> B.N >> K;
    A.read();
    B.read();

    A.run();
    B.run();

    bool die = 0;

    FOR(i,1,K){
        FOR(j,1,A.N) mn[j] = inf;
        FOR(j,1,K) if (j != i) {
            int a = A.lcd(i,j), b = B.lcd(i,j);
            mn[a] = min(mn[a],b);
        }
        RFOR(j,A.N-1,1) mn[j] = min(mn[j+1],mn[j]);
        FOR(j,1,K) if (j != i) {
            int a = A.lcd(i,j), b = B.lcd(i,j);
            if (a < A.N) die |= b > mn[a+1];
        }
    }

    cout << (die ? "NO" : "YES") << '\n';
}

• Subtask 1: 17 / 17
• Subtask 2: 27 / 27
• Subtask 3: 15 / 15
• Subtask 4: 0 / 41