Submission #714780

#	Time	Username	Problem	Language	Result	Execution time	Memory
714780		Ferid20072020	Stranded Far From Home (BOI22_island)	C++14	20 / 100	218 ms	38096 KiB

island

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//#pragma GCC optimize("O3,unroll-loops")
//#pragma GCC target("avx,avx2,fma")
 
#include <bits/stdc++.h>
 
using namespace std;
 
#define ll          long long 
#define ull         unsigned long long 
#define ld          long double 
#define ui          unsigned int 
#define f           first
#define s           second
#define ins         insert
#define pb          push_back
#define mp          make_pair
#define ln          '\n'
#define int         ll
#define pii         pair<int , int> 
#define INF         LLONG_MAX
#define vv(a)       vector<a>
#define pp(a, b)    pair<a, b>
#define pq(a)       priority_queue<a>
#define qq(a)       queue<a>
#define ss(a)       set<a>
#define mss(a)      multiset<a>
#define mm(a, b)    map<a, b>
#define mmm(a , b)  multimap<a , b>
#define sz(x)       (x).size()
#define all(x)      (x).begin() , (x).end()
#define fastio                    \
    ios_base::sync_with_stdio(0); \
    cin.tie(0);                   \
    cout.tie(0);
 
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

const int MAX = 2e5 + 3;
int n , m;
int tot[MAX];
vv(vv(int)) g(MAX);
vv(vv(pii)) g1(MAX);
vv(int) color(MAX);
vv(int) level(MAX);
vv(int) pref(MAX);
vv(int) parent(MAX);
int cnt = 0 , total = 0;

void init(){
    cnt = 1;
    total = 0;
    for(int i=1 ; i<MAX ; i++){
        color[i] = 0;
    }
}
 
void DFS(int src){
    //cout << src << ln;
    color[src] = 1;
    for(auto to : g1[src]){
        if(color[to.s] == 0 && to.f <= total){
            cnt++;
            total += to.f;
            DFS(to.s);
        }
    }
}

void DFS1(int src , int lvl){
    level[src] = lvl;
    for(auto to : g[src]){
        if(to > src){
            parent[to] = src;
            DFS1(to , lvl+1);
        }
    }
}

void solve(){
    int Max = -1e9;
    cin >> n >> m;
    if(n <= 2000 && m <= 2000){
        for(int i=1 ; i<=n ; i++){
            cin >> tot[i];
        }
        for(int i=0 ; i<m ; i++){
            int u , v;
            cin >> u >> v;
            g1[u].pb({tot[v] , v});
            g1[v].pb({tot[u] , u});
        }
        for(int i=1 ; i<=n ; i++){
            sort(all(g1[i]));
        }
        for(int i=1 ; i<=n ; i++){
            init();
            total = tot[i];
            DFS(i);
            while(cnt < n){
                int cnt1 = cnt;
                for(int j=1 ; j<=n ; j++){
                    if(color[j] == 1){
                        DFS(j);
                    }
                }
                if(cnt == cnt1){
                    break;
                }
            }
            if(cnt == n){
                cout << 1;
            }
            else{
                cout << 0;
            }
        }
    }
    else{
        for(int i=1 ; i<=n ; i++){
            cin >> tot[i];
            Max = max(Max , tot[i]);
            pref[i] = tot[i];
        }
        for(int i=0 ; i<m ; i++){
            int u , v;
            cin >> u >> v;
            g[u].pb(v);
            g[v].pb(u);
        }
        DFS1(1 , 1);
        vv(pii) Sort;
        for(int i=1 ; i<=n ; i++){
            Sort.pb({level[i] , i});
        }
        sort(all(Sort));
        reverse(all(Sort));
        for(int i=0 ; i<Sort.size() ; i++){
            pref[parent[Sort[i].s]] += pref[Sort[i].s];
        }
        reverse(all(Sort));
        for(int i=0 ; i<Sort.size() ; i++){
            if(tot[parent[Sort[i].s]] <= pref[Sort[i].s]){
                pref[Sort[i].s] = pref[parent[Sort[i].s]];
            }
        }
        //for(int i=1 ; i<=n ; i++){
        //    cout << pref[i] << ln;
        //}
        vv(int) ans(n+3 , 0);
        ans[1] = 1;
        int node = 1;
        for(int i=2 ; i<=n ; i++){
            if(pref[i] >= Max){
                ans[i] = 1;
            }
        }
        for(int i=1 ; i<=n ; i++){
            cout << ans[i];
        }
    }
}
 
 
signed main(){
    fastio
 
    int t = 1;
    //cin >> t;
    while(t--){
        solve();
    }
 
    return 0;
}

Compilation message (stderr)

island.cpp: In function 'void solve()':
island.cpp:138:24: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  138 |         for(int i=0 ; i<Sort.size() ; i++){
      |                       ~^~~~~~~~~~~~
island.cpp:142:24: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  142 |         for(int i=0 ; i<Sort.size() ; i++){
      |                       ~^~~~~~~~~~~~
island.cpp:152:13: warning: unused variable 'node' [-Wunused-variable]
  152 |         int node = 1;
      |             ^~~~

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