Submission #531173

#	Time	Username	Problem	Language	Result	Execution time	Memory
531173		KazamaHoang	Autići (COCI22_autici)	C++14	0 / 50	1022 ms	13568 KiB

Main

// no matter how hard you work, someone else is working harder
#include <bits/stdc++.h>
#define FOR(i, a, b) for (int i = (a), _i = (b); i <= _i; ++ i)
#define FORD(i, b, a) for (int i = (b), _i = (a); i >= _i; -- i)
#define REP(i, b) for (int i = 0, _i = (b); i < _i; ++ i)
#define FORE(i, a) for (auto& i : a)
#define lb lower_bound
#define ub upper_bound
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define cntbit __builtin_popcountll
#define len(x) (int)x.size()
#define bit(x, i) (((x) >> (i)) & 1)
#define all(x) x.begin(), x.end()
using namespace std;
using ll = long long;
template <typename A, typename B>
inline bool ckmax(A& a, const B& b) {
    if (a < b) {
        a = b;
        return true;
    } return false;
}
template <typename A, typename B>
inline bool ckmin(A& a, const B& b) {
    if (a > b) {
        a = b;
        return true;
    } return false;
}
inline void fileIO(const string& Task = "") {
    ios::sync_with_stdio(false); cin.tie(NULL);
    if (fopen((Task + ".inp").c_str(), "r")) {
        freopen((Task + ".inp").c_str(), "r", stdin);
        freopen((Task + ".out").c_str(), "w", stdout);
    }
}

/* Author: Hoang Quoc Viet */

/** END OF TEMPLATE **/

int n, a[100005];
int lab[100005];
vector<int> comp[100005];

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

bool unite(int u, int v) {
    u = find_set(u);
    v = find_set(v);
    if (u ^ v) {
        if (lab[u] > lab[v]) swap(u, v);
        lab[u] += lab[v];
        lab[v] = u;
        comp[u].insert(comp[u].end(), all(comp[v]));
        return true;
    } return false;
}

int main() {
    fileIO("main");

    cin >> n;
    FOR(i, 1, n) cin >> a[i];

    memset(lab, -1, sizeof lab);
    multiset<pair<int, int>> ms;
    FOR(i, 1, n) {
        comp[i].pb(i);
        ms.insert(mp(a[i], i));
    }

    ll res = 0;
    int numComp = n;
    while (numComp > 1) {
        vector<pair<int, int>> safeEdge;
        FOR(i, 1, n) if (len(comp[i])) {
            FORE(u, comp[i]) ms.erase(mp(a[u], u));
            int mn = 1e9, tmp, cur;
            FORE(u, comp[i]) {
                int x = (*ms.begin()).F;
                if (ckmin(mn, a[u] + x)) {
                    tmp = u;
                    cur = (*ms.begin()).S;
                }
            }
            FORE(u, comp[i]) ms.insert(mp(a[u], u));
            safeEdge.pb(mp(tmp, cur));
        }
        FORE(p, safeEdge) if (unite(p.F, p.S)) {
            res += a[p.F] + a[p.S];
            -- numComp;
        }
    }

    cout << res;

    return 0;
}

/*** VOI VOI VOI important things must be said three times :> ***/

Compilation message (stderr)

Main.cpp: In function 'void fileIO(const string&)':
Main.cpp:36:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   36 |         freopen((Task + ".inp").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |         freopen((Task + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp: In function 'int main()':
Main.cpp:93:36: warning: 'cur' may be used uninitialized in this function [-Wmaybe-uninitialized]
   93 |             safeEdge.pb(mp(tmp, cur));
      |                                    ^
Main.cpp:93:36: warning: 'tmp' may be used uninitialized in this function [-Wmaybe-uninitialized]

• Subtask 1: 0 / 10
• Subtask 2: 0 / 20
• Subtask 3: 0 / 20