Submission #722604

#	Time	Username	Problem	Language	Result	Execution time	Memory
722604		Itamar	Stranded Far From Home (BOI22_island)	C++14	10 / 100	1090 ms	524288 KiB

island

// ConsoleApplication134.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
using namespace std;
#include <vector>
#define vi vector<int>
#define pi pair<int,int>
#define ll long long
#include <algorithm>
#include <queue>
#define pll pair<ll,ll>
const int siz = 2e5;
bool ans[siz];
ll cit[siz];
vi fr[siz];
int up[siz];
#include <set>
vector<pll> ord;

int my[siz];
vi col[siz];
ll sum[siz];
set<pll> out[siz];

int num[siz];
void uni(int i, int j) {
    i = my[i], j = my[j];
    if (i == j)return;
    sum[i] += sum[j];
    for (pll p : out[j]) {
        out[i].insert(p);
    }
    for (int v : col[j]) {
        col[i].push_back(v);
        my[v] = i;
    }
}

int main()
{
    int n, m;
    cin >> n >> m;
    for (int i = 0; i < n; i++) {
        cin >> cit[i];
        ord.push_back({ cit[i],-i });
    }
    for (int i = 0; i < m; i++) {
        int a, b;
        cin >> a >> b;
        a--, b--;
        fr[a].push_back(b);
        fr[b].push_back(a);
    }
    sort(ord.begin(), ord.end());
    ans[-ord[n - 1].second] = 1;
    for (int i = 0; i < n; i++) {
        ord[i].second = -ord[i].second;
        num[ord[i].second] = i;
    }
    for (int i = 0; i < n; i++) {
        my[i] = i;
        col[i].push_back(i);
        sum[i] = cit[i];
        
        for (int f : fr[i]) {
            if ( num[f]>num[i]) {
                out[i].insert({ cit[f],f });
            }
        }
    }                
    for (int i = 0; i < n; i++)up[i] = -1;
    for (int i = 0; i < n-1; i++) {
        int j = ord[i].second;
        for (int f : fr[j]) {
            if (out[my[f]].find({ cit[j],j }) != out[my[f]].end()) {
                out[my[f]].erase({ cit[j],j });
            }
        }
        for (int f : fr[j]) {
            if (num[f] < i) {
                uni(j, f);
            }
        }
        if (!out[my[j]].empty()) {
            pll p = *out[my[j]].begin();
            if (p.first <= sum[my[j]]) {
                up[j] = p.second;
            }
        }
    }
    for (int i = n - 2; i >= 0; i--) {
        if (up[ord[i].second] != -1) {
            ans[ord[i].second] = ans[up[ord[i].second]];
        }
    }
    for (int i = 0; i < n; i++)if (ans[i])cout << '1'; else cout << '0';
}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started: 
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file

• Subtask 1: 10 / 10
• Subtask 2: 0 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 30
• Subtask 5: 0 / 35