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답안 #399347

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
399347 2021-05-05T15:33:34 Z 12tqian Worst Reporter 4 (JOI21_worst_reporter4) C++17
14 / 100
 23 ms 2508 KB 
#include <bits/stdc++.h>

using namespace std;

#define f1r(i, a, b) for (int i = a; i < b; ++i)
#define f0r(i, a) f1r(i, 0, a)
#define each(t, a) for (auto& t : a)

#define mp make_pair
#define f first
#define s second
#define pb push_back
#define eb emplace_back
#define sz(x) (int)(x).size()
#define all(x) begin(x), end(x)

typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;

template <class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template <class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }

template <class T> int get_pos(vector<T> v, T x) {
    return lower_bound(all(v), x) - v.begin();
}

const int N = 2e5 + 5;

struct DSU {
    vi e;
    
    void init(int n) {
        e = vi(n, -1);
    }

    int get(int x) {
        return e[x] < 0 ? x : e[x] = get(e[x]);
    }

    int size(int x) {
        return -e[get(x)];
    }

    bool unite(int x, int y) {
        x = get(x), y = get(y);
        if (x == y) return false;
        if (e[x] > e[y]) swap(x, y);
        e[x] += e[y]; e[y] = x;
        return true;
    }
};


int main() {
    cin.tie(0)->sync_with_stdio(0);
    int n; cin >> n;
    vi a(n);
    vi h(n);
    vl c(n);
    vector<bool> vis(n);
    vector<bool> cyc(n);
    vi tmp;
    f0r(i, n) {
        cin >> a[i] >> h[i] >> c[i];
        --a[i];
        tmp.pb(h[i]);
    }
    sort(all(tmp));
    tmp.erase(unique(all(tmp)), tmp.end());
    f0r(i, n) h[i] = get_pos(tmp, h[i]);
    f0r(i, n) h[i] = sz(tmp) - 1 - h[i];
    DSU D; D.init(n);
    if (n > 5000) return 0;
    f0r(i, n) {
        if (vis[i]) continue;
        int cur = i;
        vi path;
        while (!vis[cur]) {
            vis[cur] = true;
            path.pb(cur);
            cur = a[cur];
        }
        int loc = -1;
        f0r(i, sz(path)) {
            if (path[i] == cur) {
                loc = i;
                break;
            }
        }
        if (loc == -1) continue;
        f1r(i, loc, sz(path)) {
            cyc[path[i]] = true;
            D.unite(cur, path[i]);
        }
    }
    vi v;
    f0r(i, n) v.pb(D.get(i));
    sort(all(v));
    v.erase(unique(all(v)), v.end());
    vi id(n);
    f0r(i, n) id[i] = get_pos(v, D.get(i));
    int sz = sz(v);
    vector<map<int, ll>> dp(sz);
    vector<vi> comps(sz);
    f0r(i, n) {
        comps[id[i]].pb(i);
    }
    vi roots;
    each(x, v) {
        if (cyc[comps[get_pos(v, x)][0]]) {
            roots.pb(get_pos(v, x));
        }
    }
    vector<vi> g(sz);
    f0r(i, n) {
        int x = id[i];
        int y = id[a[i]];
        if (x == y) continue;
        g[x].pb(y);
        g[y].pb(x);
    }
    ll ans = 0;
    each(r, roots) {
        function<void(int, int)> dfs = [&](int u, int p) {
            each(v, g[u]) {
                if (v == p) continue;
                dfs(v, u);
                if (sz(dp[v]) > sz(dp[u])) swap(dp[u], dp[v]);
                each(x, dp[v]) {
                    dp[u][x.f] += x.s;
                }
            } 
            // add the root
            auto& st = dp[u];
            if (u == r) {
                auto it = st.begin();
                while (it != st.end()) {
                    if (it != st.begin()) {
                        it->s += prev(it)->s;
                    }
                    it = next(it);
                }
                map<int, ll> cost;
                each(vert, comps[u]) {
                    cost[h[vert]] += c[vert];
                }
                ll mx = 0;
                if (sz(st)) mx = st.rbegin()->s;
                each(vert, cost) {
                    int d = vert.f;
                    ll v = vert.s;
                    it = st.upper_bound(d);
                    if (it != st.begin()) {
                        ckmax(mx, prev(it)->s + v);
                    }
                    ckmax(mx, v);
                }
                ans += mx;
            } else {
                int vert = comps[u][0];
                int d = h[vert];
                ll v = c[vert];
                st[d] += v;
                auto it = st.upper_bound(d);
                while (it != st.end() && v) {
                    ll rem = min(v, it->s);
                    it->s -= rem;
                    v -= rem;
                    if (it->s == 0) {
                        it = next(it);
                        st.erase(prev(it));
                    }
                }
            }
        };
        dfs(r, -1);
    }
    ll sum = 0;
    f0r(i, n) sum += c[i];
    ans = sum - ans;
    cout << ans << '\n';
    return 0;
}

/**
 * goes to a[i]
 * maximize the cost if decreasing subsequences up the tree
 * let's consider the cycle at the very end
 * then there is a cost associated with each possible value at the top
 * and a cost associated with nothing
 * first consider the case of fixed
 * things decrease from the root
 * this means that in increasing order it's better
 */

Subtask #1
14.0 / 14.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 208 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 22 ms 2128 KB Output is correct
6 Correct 16 ms 1788 KB Output is correct
7 Correct 15 ms 1484 KB Output is correct
8 Correct 23 ms 2244 KB Output is correct
9 Correct 16 ms 1796 KB Output is correct
10 Correct 15 ms 1484 KB Output is correct
11 Correct 14 ms 1356 KB Output is correct
12 Correct 20 ms 2184 KB Output is correct
13 Correct 15 ms 2176 KB Output is correct
14 Correct 20 ms 1660 KB Output is correct
15 Correct 15 ms 1668 KB Output is correct
16 Correct 23 ms 2508 KB Output is correct
17 Correct 16 ms 1996 KB Output is correct
18 Correct 14 ms 1484 KB Output is correct
19 Correct 22 ms 2056 KB Output is correct
20 Correct 15 ms 1868 KB Output is correct
21 Correct 14 ms 1804 KB Output is correct
22 Correct 20 ms 1868 KB Output is correct
23 Correct 15 ms 1576 KB Output is correct
24 Correct 21 ms 1988 KB Output is correct
25 Correct 15 ms 1868 KB Output is correct
26 Correct 19 ms 2116 KB Output is correct
27 Correct 20 ms 2052 KB Output is correct
28 Correct 20 ms 2112 KB Output is correct
29 Correct 21 ms 2228 KB Output is correct
30 Correct 20 ms 2112 KB Output is correct
31 Correct 21 ms 2176 KB Output is correct

Subtask #2
0 / 65.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 7 ms 332 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 21.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 208 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 1 ms 204 KB Output is correct
5 Correct 22 ms 2128 KB Output is correct
6 Correct 16 ms 1788 KB Output is correct
7 Correct 15 ms 1484 KB Output is correct
8 Correct 23 ms 2244 KB Output is correct
9 Correct 16 ms 1796 KB Output is correct
10 Correct 15 ms 1484 KB Output is correct
11 Correct 14 ms 1356 KB Output is correct
12 Correct 20 ms 2184 KB Output is correct
13 Correct 15 ms 2176 KB Output is correct
14 Correct 20 ms 1660 KB Output is correct
15 Correct 15 ms 1668 KB Output is correct
16 Correct 23 ms 2508 KB Output is correct
17 Correct 16 ms 1996 KB Output is correct
18 Correct 14 ms 1484 KB Output is correct
19 Correct 22 ms 2056 KB Output is correct
20 Correct 15 ms 1868 KB Output is correct
21 Correct 14 ms 1804 KB Output is correct
22 Correct 20 ms 1868 KB Output is correct
23 Correct 15 ms 1576 KB Output is correct
24 Correct 21 ms 1988 KB Output is correct
25 Correct 15 ms 1868 KB Output is correct
26 Correct 19 ms 2116 KB Output is correct
27 Correct 20 ms 2052 KB Output is correct
28 Correct 20 ms 2112 KB Output is correct
29 Correct 21 ms 2228 KB Output is correct
30 Correct 20 ms 2112 KB Output is correct
31 Correct 21 ms 2176 KB Output is correct
32 Incorrect 7 ms 332 KB Output isn't correct
33 Halted 0 ms 0 KB -