Submission #1048754

#	Time	Username	Problem	Language	Result	Execution time	Memory
1048754		Plurm	September (APIO24_september)	C++17	59 / 100	139 ms	19500 KiB

september

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

vector<vector<int>> g;
vector<vector<int>> mxn;
vector<vector<int>> bck;
void dfs(int u){
    for(int v : g[u]) dfs(v);
    for(int i = 0; i < bck.size(); i++){
        mxn[i][u] = bck[i][u];
        for(int v : g[u]){
            mxn[i][u] = max(mxn[i][u], mxn[i][v]);
        }
    }
}
vector<int> rndperm;
const int MOD = 1e9+7;
class HashedSet{
public:
    int a, b, c, d, e;
    HashedSet() : a(0), b(1), c(0), d(1000000000), e(0) {}
    void insert(int x){
        a += rndperm[x];
        a %= MOD;
        b = 1ll * b * rndperm[x] % MOD;
        c = max(c, rndperm[x]);
        d = min(d, rndperm[x]);
        e ^= rndperm[x];
    }
    friend bool operator!=(const HashedSet& h1, const HashedSet& h2){
        return h1.a != h2.a || h1.b != h2.b || h1.c != h2.c || h1.d != h2.d || h1.e != h2.e;
    }
};
int solve(int N, int M, vector<int> F, vector<vector<int>> S) {
    if(rndperm.empty()){
        rndperm.resize(100005);
        default_random_engine dre;
        dre.seed(time(NULL));
        uniform_int_distribution<int> uid(2, 1000000000);
        for(int i = 0; i <= 100000; i++) rndperm[i] = uid(dre);
    }
    g.resize(N);
    for(int i = 1; i < N; i++){
        g[F[i]].push_back(i);
    }
    bck.resize(M);
    mxn.resize(M);
    for(int i = 0; i < M; i++){
        bck[i].resize(N);
        mxn[i].resize(N);
        for(int j = 0; j < N-1; j++){
            bck[i][S[i][j]] = j;
        }
    }
    dfs(0);
    int k = 0;
    int l = 0;
    while(l < N-1){
        // left: l
        vector<set<int>> ss(M);
        int mnr = l-1;
        int i = l;
        bool ok = true;
        do{
            mnr++;
            if(mnr >= N-1) exit(-1);
            while(i <= mnr){
                for(int j = 0; j < M; j++){
                    ss[j].insert(S[j][i]);
                    mnr = max(mnr, mxn[j][S[j][i]]);
                }
                i++;
            }
            for(int j = 1; j < M; j++) if(ss[j] != ss[0]) ok = false;
        }while(!ok);
        l = mnr+1;
        k++;
    }
    g.clear();
    bck.clear();
    mxn.clear();
	return k;
}

Compilation message (stderr)

september.cpp: In function 'void dfs(int)':
september.cpp:10:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |     for(int i = 0; i < bck.size(); i++){
      |                    ~~^~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 0 / 14
• Subtask 3: 5 / 5
• Subtask 4: 9 / 9
• Subtask 5: 5 / 5
• Subtask 6: 0 / 11
• Subtask 7: 9 / 9
• Subtask 8: 11 / 11
• Subtask 9: 9 / 9
• Subtask 10: 0 / 16