Submission #1174906

#	Time	Username	Problem	Language	Result	Execution time	Memory
1174906		dzhoz0	지구 온난화 (NOI13_gw)	C++20	40 / 40	176 ms	31612 KiB

gw

#include <bits/stdc++.h>
using namespace std;

#define int long long
#define INF 1e18
#define f first
#define s second
#define pii pair<int, int>
#define vi vector<int>

const int MOD = 1'000'000'000 + 7;

void setIO(string name = "")
{
    ios_base::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
#ifdef LOCAL
    freopen("inp.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
#else
    if (!name.empty())
    {
        freopen((name + ".INP").c_str(), "r", stdin);
        freopen((name + ".OUT").c_str(), "w", stdout);
    }
#endif
}

// START OF DEBUG
#define db(val) "["#val" = "<<(val)<<"] "
#define print_op(...) ostream& operator<<(ostream& out, const __VA_ARGS__& u)
// for printing std::pair
template<class U, class V> print_op(pair<U, V>) {
    return out << "(" << u.first << ", " << u.second << ")";
}
// for printing collection
template<class Con, class = decltype(begin(declval<Con>()))>
typename enable_if<!is_same<Con, string>::value, ostream&>::type
operator<<(ostream& out, const Con& con) { 
    out << "{";
    for (auto beg = con.begin(), it = beg; it != con.end(); ++it)
        out << (it == beg ? "" : ", ") << *it;
    return out << "}";
}
// for printing std::tuple
template<size_t i, class T> ostream& print_tuple_utils(ostream& out, const T& tup) {
    if constexpr(i == tuple_size<T>::value) return out << ")"; 
    else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); 
}
template<class ...U> print_op(tuple<U...>) {
    return print_tuple_utils<0, tuple<U...>>(out, u);
}
// END OF DEBUG

const int MAXN = 1e6;
int par[MAXN + 5];
int sz[MAXN + 5];
int numCmps = 0;
void make_set(int v) {
    par[v] = v;
    sz[v] = 1;
    numCmps++;
}

int find_set(int v) {
    if(par[v] == v) return v;
    return par[v] = find_set(par[v]);
}

void union_set(int u, int v) {
    u = find_set(u);
    v = find_set(v);
    if(u != v) {
        if(sz[u] < sz[v]) swap(u, v);
        par[v] = u;
        sz[u] += sz[v];
        numCmps--;
    }
}

void solve()
{
    int n; cin >> n;
    vector<pii> v(n);
    for(int i = 0; i < n; i++) {
        cin >> v[i].f;
        v[i].s = i;
        par[i] = -1;
    }
    sort(v.rbegin(), v.rend());
    // cout << v << '\n';

    int res = 0;
    for(int x = 0; x < n; x++) {
        int i = v[x].s;
        // cout << db(i) << '\n';
        make_set(i);
        for(int j : {i - 1, i + 1}) {
            if(j >= 0 && j < n) {
                if(par[j] != -1) {
                    // cout << i << ' ' << j << '\n';
                    // cout << par[j] << '\n';
                    union_set(i, j);
                }
            }
        }
        if(x == n - 1 || v[x].f != v[x + 1].f) {
            // cout << db(i) << ' ' << db(numCmps) << '\n';
            res = max(res, numCmps);
        }
    }
    cout << res << '\n';
}
signed main()
{
    setIO();
    int t = 1;
    // cin >> t;
    while (t--)
        solve();
}

Compilation message (stderr)

gw.cpp: In function 'void setIO(std::string)':
gw.cpp:23:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |         freopen((name + ".INP").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
gw.cpp:24:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   24 |         freopen((name + ".OUT").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 6 / 6
• Subtask 3: 7 / 7
• Subtask 4: 10 / 10
• Subtask 5: 11 / 11