Submission #1041244

#	Time	Username	Problem	Language	Result	Execution time	Memory
1041244		Marco_Escandon	Stranded Far From Home (BOI22_island)	C++11	100 / 100	223 ms	45756 KiB

island

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define x first
#define y second
struct DSUF{
    vector<ll> P,S;
    vector<vector<ll>> E;
    ll Find(ll i){
        if(i==P[i]) return i;
        return P[i]=Find(P[i]);
    }
    void Union(ll a, ll b){
        a=Find(a);
        b=Find(b);
        if(a==b) return;
        if(S[a]<S[b])swap(a,b);
        S[a]+=S[b]; P[b]=a;
        for(auto i:E[b]) E[a].push_back(i);
    }
    bool Same(ll a, ll b) { return (Find(a)==Find(b)); }
    ll Size(ll a) { return S[a]; }
    DSUF(ll n,vector<ll> cad)
    {
        P.assign(n+5,0);
        S.assign(n+5,0);
        E.resize(n+5);
        for(int i=1; i<=n; i++)
            S[i]=cad[i];
        for(int i=0; i<P.size(); i++){
            P[i]=i;   
            E[i].push_back(i);
        }
    }
};
int main()
{
    ll n,m;
    cin>>n>>m;
    vector<ll> cad(n+1);
    vector<ll>sol(n+1,0);
    for(int i=1; i<=n; i++)
        cin>>cad[i];
    priority_queue<pair<ll,pair<ll,ll>>> q;
    for(int i=0; i<m; i++)
    {
        ll a,b;
        cin>>a>>b;
        if(cad[a]<cad[b]) swap(a,b);
        q.push({-cad[a],{a,b}});
    }
    DSUF asd(n,cad);
    while (!q.empty())
    {
        ll a=q.top().x;
        vector<pair<ll,ll>> temp;
        while(!q.empty()&&q.top().x==a){
            temp.push_back(q.top().y);
            q.pop();
        }
        for(int i=0; i<temp.size(); i++)
        {
            temp[i].x=asd.Find(temp[i].x);
            temp[i].y=asd.Find(temp[i].y);
        }
        sort(temp.begin(),temp.end());
        vector<pair<ll,ll>> temp2;temp2.push_back(temp[0]);
        for(int i=1; i<temp.size(); i++)
            if(temp[i]!=temp[i-1])
                temp2.push_back(temp[i]);
        for(auto i:temp2)
            if(asd.Size(i.y)<cad[i.x])
                asd.E[i.y].clear();
        for(auto i:temp2)
                asd.Union(i.x,i.y);
    }
    for(auto i:asd.E[asd.Find(1)])
        sol[i]=1;
        
    for(int i=1; i<=n; i++)
        cout<<sol[i];
    return 0;
}

Compilation message (stderr)

island.cpp: In constructor 'DSUF::DSUF(ll, std::vector<long long int>)':
island.cpp:30:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |         for(int i=0; i<P.size(); i++){
      |                      ~^~~~~~~~~
island.cpp: In function 'int main()':
island.cpp:61:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   61 |         for(int i=0; i<temp.size(); i++)
      |                      ~^~~~~~~~~~~~
island.cpp:68:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |         for(int i=1; i<temp.size(); i++)
      |                      ~^~~~~~~~~~~~

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