Submission #711162

#	Time	Username	Problem	Language	Result	Execution time	Memory
711162		rrrr10000	Stranded Far From Home (BOI22_island)	C++14	100 / 100	344 ms	31620 KiB

island

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> vi;
typedef vector<vi> vvi;
typedef pair<ll,ll> P;
typedef tuple<ll,ll,ll> PP;
typedef vector<P> vp;
typedef vector<vp> vvp;
#define rep(i,n) for(ll i=0;i<(ll)(n);i++)
#define REP(i,k,n) for(ll i=(ll)(k);i<(ll)(n);i++)
#define all(a) a.begin(),a.end()
#define fi first
#define se second
#define pb emplace_back
template<class T> void out(T a){cout<<a<<endl;}
template<class T> void outv(T v){rep(i,v.size()){if(i)cout<<' ';cout<<v[i];}cout<<endl;}
template<class T> void outvv(T v){for(auto x:v)outv(x);}
template<class T> void outvp(T v){rep(i,v.size()){cout<<'('<<v[i].fi<<','<<v[i].se<<')';}cout<<endl;}
template<class T> void outvvp(T v){for(auto x:v)outvp(x);}
struct UF{
    vi par;
    UF(ll n):par(n,-1){}
    ll root(ll i){
        if(par[i]==-1)return i;
        par[i]=root(par[i]);
        return par[i];
    }
};
int main(){
    ll n,m;cin>>n>>m;
    vi v(n);rep(i,n)cin>>v[i];
    vector<PP> srt(m);
    rep(i,m){
        ll a,b;cin>>a>>b;a--;b--;
        if(P(v[a],a)<P(v[b],b))swap(a,b);
        srt[i]=PP(v[a],a,b);
    }
    sort(all(srt));
    UF uf(n);
    vvi ch(n);
    for(auto x:srt){
        ll t,a,b;tie(t,a,b)=x;
        b=uf.root(b);
        if(a==b)continue;
        ch[a].pb(b);
        uf.par[b]=a;
    }
    ll rt=uf.root(0);
    vi sub(n);
    auto dfs=[&](auto && self,ll i) -> void {
        sub[i]=v[i];
        for(ll x:ch[i]){
            self(self,x);
            sub[i]+=sub[x];
        }
    };dfs(dfs,rt);
    string ans(n,'0');
    auto dfs2=[&](auto && self,ll i) -> void {
        ans[i]='1';
        for(ll x:ch[i])if(sub[x]>=v[i]){
            self(self,x);
        }
    };dfs2(dfs2,rt);
    out(ans);
}

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