Submission #863995

#	Time	Username	Problem	Language	Result	Execution time	Memory
863995		nnhzzz	Evacuation plan (IZhO18_plan)	C++14	100 / 100	551 ms	60256 KiB

plan

// cre: Nguyen Ngoc Hung - Train VOI 2024

#include<bits/stdc++.h>

using namespace std;

#define        __nnhzzz__  signed main()
#define          BIT(i,j)  ((i>>j)&1LL)
#define           MASK(i)  (1LL<<i)
#define            ALL(x)  (x).begin(),(x).end()
#define             SZ(x)  (int)(x).size()
#define               gcd  __gcd
#define                fi  first
#define                se  second
#define                ll  long long
#define               ull  unsigned long long
#define                ld  long double
#define                vi  vector<int>
#define               vvi  vector<vi>
#define              vvvi  vector<vvi>
#define               pii  pair<int,int>
#define              vpii  vector<pii>
#define        REP(i,a,b)  for(int i = (a); i<=(b); ++i)
#define       REPD(i,a,b)  for(int i = (a); i>=(b); --i)
#define   REPDIS(i,a,b,c)  for(int i = (a); i<=(b); i+=c)
#define              endl  "\n"
#define               int  ll
#define                MP  make_pair

//-------------------------------------------------------------//
const int oo = 1e9,LOG = 20,MAXN = 2e5+7,N = 1e2+3,inf = 1e15;
const int MOD = 1e9+7,MOD1 = 1e9+207,MOD2 = 1e9+407,MOD3 = 998244353;
//-------------------------------------------------------------//
template<typename T> bool mini(T &a, const T &b){if(a>b){a=b;return true;}return false;}
template<typename T> bool maxi(T &a, const T &b){if(a<b){a=b;return true;}return false;}

/*
----------------------------------------------------------------
    END OF TEMPLATE
----------------------------------------------------------------
    Nguyen Ngoc Hung - nnhzzz
    Training for VOI24 gold medal
----------------------------------------------------------------
*/

int res[MAXN];
vpii adj[MAXN];
vi spec;
int n,m,k,q,now = 0;

struct DSU
{
    vi par;
    vector<set<int>> se;
    int n;

    int find(int u){
        return u==par[u]?u:par[u]=find(par[u]);
    }

    int same(int u, int v){
        return find(u)==find(v);
    }

    bool unite(int u, int v){
        u = find(u); v = find(v);
        if(u==v) return false;
        if(SZ(se[u])<SZ(se[v])) swap(u,v);
        vi tmp;
        for(const auto &i:se[v]){
            if(SZ(se[u])==0) break;
            auto it = se[u].find(i);
            if(it==se[u].end()){
                se[u].insert(i);
                continue;
            }
            se[u].erase(it);
            tmp.push_back(i);
            res[i] = now;
        }
        for(const auto &i:tmp) se[v].erase(i);
        par[v] = u;
        se[v].clear();
        return true;
    }

    DSU(int _n):n(_n){
        par.assign(n+3,0); iota(ALL(par),0);
        se.assign(n+3,set<int>());
    }
};

void solve(){
    cin >> n >> m;
    REP(i,1,m){
        int u,v,w; cin >> u >> v >> w;
        adj[u].emplace_back(v,w);
        adj[v].emplace_back(u,w);
    }
    cin >> k;
    REP(i,1,k){
        int u; cin >> u;
        spec.push_back(u);
    }
    priority_queue<pii,vpii,greater<pii>> heap;
    vi dis(n+3,inf);
    for(const auto &u:spec){
        dis[u] = 0;
        heap.emplace(0,u);
    }
    while(SZ(heap)!=0){
        int w1 = heap.top().fi,u = heap.top().se; heap.pop();
        if(dis[u]!=w1) continue;
        REP(i,0,SZ(adj[u])-1){
            int w = adj[u][i].se,v = adj[u][i].fi;
            if(mini(dis[v],dis[u]+w)){
                heap.emplace(dis[v],v);
            }
        }
    }
    vector<pair<int,pii>> e;
    REP(u,1,n){
        REP(i,0,SZ(adj[u])-1){
            int v = adj[u][i].fi;
            if(u>v) continue;
            e.push_back(MP(min(dis[u],dis[v]),MP(u,v)));
        }
    }
    sort(ALL(e)); reverse(ALL(e));
    DSU dsu(n);
    cin >> q;
    REP(i,1,q){
        int s,t; cin >> s >> t;
        dsu.se[s].insert(i);
        dsu.se[t].insert(i);
    }
    REP(i,0,SZ(e)-1){
        int w = e[i].fi,u = e[i].se.fi,v = e[i].se.se;
        if(dsu.same(u,v)==false){
            now = w;
            dsu.unite(u,v);
        }
    }
    REP(i,1,q) cout << res[i] << endl;
}

__nnhzzz__{
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    #define name "test"
    if(fopen(name".inp","r")){
        freopen(name".inp","r",stdin);
        freopen(name".out","w",stdout);
    }
    #define name1 "nnhzzz"
    if(fopen(name1".inp","r")){
        freopen(name1".inp","r",stdin);
        freopen(name1".out","w",stdout);
    }
    int test = 1;
    while(test--){
        solve();
    }
    cerr << "\nTime elapsed: " << 1000*clock()/CLOCKS_PER_SEC << "ms\n";
    return 0;
}

Compilation message (stderr)

plan.cpp: In function 'int main()':
plan.cpp:152:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  152 |         freopen(name".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
plan.cpp:153:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  153 |         freopen(name".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
plan.cpp:157:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  157 |         freopen(name1".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
plan.cpp:158:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  158 |         freopen(name1".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 19 / 19
• Subtask 5: 46 / 46