Submission #1287033

#	Time	Username	Problem	Language	Result	Execution time	Memory
1287033		nlhuy	Stranded Far From Home (BOI22_island)	C++20	100 / 100	210 ms	36896 KiB

island

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

#define ll long long
#define fi first
#define se second
#define Task "test"

typedef pair<int,int>ii;

const int MOD = 1e9+7;
const int INF = 1e9+7;
const int Maxn = 2e5+7;
const int di[] = {0, 0, -1, 1};
const int dj[] = {-1, 1, 0, 0};

vector<int>node[Maxn],g[Maxn];
ll sum[Maxn];
int par[Maxn],res[Maxn];
bool vis[Maxn];
ii a[Maxn]; 

void make_set(int n){
    for(int i=1;i<=n;i++) par[i]=i,node[i].push_back(i),sum[i]=a[i].fi;
}

int find_set(int x){
    if (x==par[x]) return x;
    return par[x]=find_set(par[x]);
}

void unite(int a,int b){
    a=find_set(a);
    b=find_set(b);
    if (a==b) return;
    if (node[a].size()<node[b].size()) swap(a,b);
    sum[a]+=sum[b];
    for(int x:node[b]) node[a].push_back(x);
    par[b]=a;
}

void run_case(){
    int n,m;
    cin>>n>>m;
    for(int i=1;i<=n;i++) cin>>a[i].fi,a[i].se=i;
    while(m--){
        int u,v;
        cin>>u>>v;
        g[u].push_back(v);
        g[v].push_back(u);
    }
    make_set(n);
    sort(a+1,a+n+1);
    for(int i=1;i<=n;i++) res[i]=1,vis[i]=0;
    for(int i=1;i<=n;i++){
        vis[a[i].se]=1;
        for(int v:g[a[i].se]){
            if (vis[v]){
                int u=find_set(v);
                if (sum[u]<a[i].fi){
                    for(int x:node[u]) res[x]=0;
                }
            }
        }
        for(int v:g[a[i].se]){
            if (vis[v]) unite(a[i].se,v);
        }
    }
    for(int i=1;i<=n;i++) cout<<res[i];
}
int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    if (fopen(Task ".inp", "r"))
    {
        freopen(Task ".inp", "r", stdin);
        freopen(Task ".out", "w", stdout);
    }
    int t = 1;
    //cin >> t;
    while(t--){
        run_case();
    }
}

Compilation message (stderr)

island.cpp: In function 'int main()':
island.cpp:75:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   75 |         freopen(Task ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
island.cpp:76:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   76 |         freopen(Task ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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