Submission #1099408

#	Time	Username	Problem	Language	Result	Execution time	Memory
1099408		Requiem	Sightseeing (NOI14_sightseeing)	C++17	15 / 25	132 ms	54352 KiB

sightseeing

#include<bits/stdc++.h>
#define int long long
#define pb push_back
#define fast ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
#define MOD 1000000007
#define inf 1e18
#define fi first
#define se second
#define FOR(i,a,b) for(int i=a;i<=b;i++)
#define FORD(i,a,b) for(int i=a;i>=b;i--)
#define sz(a) ((int)(a).size())
#define endl '\n'
#define pi 3.14159265359
#define TASKNAME "sightseeing"
using namespace std;
template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return true; }; return false; }
template<typename T> bool minimize(T &res, const T &val) { if (res > val){ res = val; return true; }; return false; }
typedef pair<int,int> ii;
typedef pair<int,ii> iii;
typedef vector<int> vi;
const int MAXN = 5e5 + 9;
int n, m, k;
iii edge[MAXN];

struct DSU{
    vector<int> lab;
    DSU(int sz = 0){
        lab.resize(sz + 9, -1);
    }

    int root(int u){
        return (lab[u] < 0) ? u : lab[u] = root(lab[u]);
    }

    bool unite(int u, int v){
        u = root(u);
        v = root(v);
        if (u != v){
            if (lab[u] > lab[v]) swap(u, v);
            lab[u] += lab[v];

            lab[v] = u;
            return true;
        }
        return false;
    }
};

DSU D;
vector<int> g[MAXN];
int answer[MAXN];

void dfs(int u, int p, int d){
    answer[u] = d;
    for(int id: g[u]){
        int w = edge[id].fi;
        int v = edge[id].se.fi + edge[id].se.se - u;
        if (v == p) continue;
        dfs(v, u, min(d, w));
    }
}
main()
{
    fast;
    if (fopen(TASKNAME".inp","r")){
        freopen(TASKNAME".inp","r",stdin);
        freopen(TASKNAME".out","w",stdout);
    }
    cin >> n >> m >> k;
    FOR(i, 1, m){
        cin >> edge[i].se.fi >> edge[i].se.se >> edge[i].fi;
    }
    sort(edge + 1, edge + 1 + m, [&](const iii &a, const iii &b){
         return a.fi > b.fi;
    });

    D = DSU(n);
    FOR(i,1, m){
        if (D.unite(edge[i].se.fi, edge[i].se.se)){
            g[edge[i].se.fi].pb(i);
            g[edge[i].se.se].pb(i);
//            cout << edge[i].se.se << ' ' << edge[i].se.fi<< endl;
        }
    }
    dfs(1, -1, inf);
    FOR(i, 1, k){
        int u;
        cin >> u;
        cout << answer[u] << endl;
    }



}
/**
Warning:
Cận lmao
Code imple thiếu case nào không.
Limit.
**/

Compilation message (stderr)

sightseeing.cpp:62:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   62 | main()
      | ^~~~
sightseeing.cpp: In function 'int main()':
sightseeing.cpp:66:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   66 |         freopen(TASKNAME".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
sightseeing.cpp:67:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   67 |         freopen(TASKNAME".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 4 / 4
• Subtask 2: 5 / 5
• Subtask 3: 6 / 6
• Subtask 4: 0 / 10