Submission #1101685

#	Time	Username	Problem	Language	Result	Execution time	Memory
1101685		pubin06	Stranded Far From Home (BOI22_island)	C++14	10 / 100	13 ms	6320 KiB

island

#include <bits/stdc++.h>
#define int long long
#define fi first
#define se second
#define sz(v) (int)(v).size()
using namespace std;

const int MXn = 100005;
const long long oo = 1e18;
const int MOD = 1e9 + 7;

int n, m, a[MXn], s[MXn], par[MXn];
bool cant[MXn];
int find_par(int u) {
	if (u == par[u]) return u;
	int r = find_par(par[u]);
	cant[u] |= cant[par[u]];
	return par[u] = r;
}

signed main(void) {
    ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
    
    #define TASK ""
    if (ifstream(TASK".INP")) {
    	freopen(TASK".INP", "r", stdin);
    	freopen(TASK".OUT", "w", stdout);
    }
    
    cin >> n >> m;
    for (int i = 1; i <= n; i++) cin >> a[i], s[i] = a[i];
    iota(par + 1, par + 1 + n, 1);
    vector<array<int, 3>> es;
    for (int i = 1, u, v; i <= m; i++) {
    	cin >> u >> v;
    	if (a[u] < a[v]) swap(u, v);
    	es.push_back({a[u], u, v});
    }
    sort(begin(es), end(es));
    for (auto e: es) {
    	int u = e[1], v = e[2];
    	u = find_par(u), v = find_par(v);
    	if (u ^ v) {
    		cant[v] = s[v] < a[u];
    		s[u] += s[v];
    		par[v] = u;
    	}
    }
    for (int i = 1; i <= n; i++) {
    	find_par(i); cout << (cant[i] ? 0 : 1);
    }
    
    return 0;
}

Compilation message (stderr)

island.cpp: In function 'int main()':
island.cpp:26:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |      freopen(TASK".INP", "r", stdin);
      |      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
island.cpp:27:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |      freopen(TASK".OUT", "w", stdout);
      |      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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