Submission #622383

#	Time	Username	Problem	Language	Result	Execution time	Memory
622383		happypotato	Connecting Supertrees (IOI20_supertrees)	C++17	11 / 100	1193 ms	1871404 KiB

supertrees

#include "supertrees.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int, int>
#define ff first
#define ss second
#define pb push_back
//
const int mxN = 1001;
vector<vector<int>> paths;
int n;
bool st1() {
    vector<vector<int>> ans;
    ans.resize(n);
    for (int i = 0; i < n; i++) ans[i].resize(n);
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            ans[i][j] = (abs(i - j) == 1);
        }
    }
    build(ans);
    return true;
}
bool vis[mxN];
void resetvis() {
    for (int i = 0; i < n; i++) vis[i] = false;
}
vector<vector<int>> components;
vector<int> curcomponent;
void dfs(int u, int tar) {
    curcomponent.pb(u);
    vis[u] = true;
    for (int v = 0; v < n; v++) {
        if (u != v && 1 <= paths[u][v] && paths[u][v] <= tar) {
            dfs(v, tar);
        }
    }
}
int rep[mxN];
int repcnt = 1;
bool fullsol() {
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if (paths[i][j] == 3) return false;
        }
    }
    for (int i = 0; i < n; i++) {
        if (!vis[i]) {
            dfs(i, 2);
            components.pb(curcomponent);
            curcomponent.clear();
        }
    }
    vector<vector<int>> ans(n);
    for (int i = 0; i < n; i++) ans[i].resize(n, 0);
    vector<vector<int>> decomp;
    for (vector<int> &cur : components) {
        decomp.clear();
        for (int &u : cur) {
            for (int &v : cur) {
                if (!vis[u] && paths[u][v] == 1) {
                    dfs(u, 1);
                    for (int &x : curcomponent) rep[x] = repcnt;
                    repcnt++;
                    decomp.pb(curcomponent);
                    curcomponent.clear();
                    break;
                }
            }
            if (!vis[u]) decomp.pb({u});
        }
        for (int &u : cur) {
            for (int &v : cur) {
                if (paths[u][v] != 1 + (rep[u] != rep[v])) return false;
            }
        }
        for (vector<int> &process : decomp) {
            for (int i = 1; i < process.size(); i++) {
                ans[process[i - 1]][process[i]] = 1;
            }
        }
        if (decomp.size() >= 2) {
            for (int i = 1; i < decomp.size(); i++) {
                ans[decomp[i - 1][0]][decomp[i][0]] = 1;
            }
            ans[decomp.front()[0]][decomp.back()[0]] = 1;
        }
    }
    build(ans);
    return true;
}
int construct(vector<vector<int>> p) {
    n = p.size(); paths = p;
    int st = 0;
    for (vector<int> &curv : p) {
        for (int &cur : curv) {
            st |= (1 << cur);
        }
    }
    if (st == 2) return st1();
    else return fullsol();
}

Compilation message (stderr)

supertrees.cpp: In function 'bool fullsol()':
supertrees.cpp:79:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   79 |             for (int i = 1; i < process.size(); i++) {
      |                             ~~^~~~~~~~~~~~~~~~
supertrees.cpp:84:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   84 |             for (int i = 1; i < decomp.size(); i++) {
      |                             ~~^~~~~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 0 / 10
• Subtask 3: 0 / 19
• Subtask 4: 0 / 35
• Subtask 5: 0 / 21
• Subtask 6: 0 / 4