Submission #782728

#	Time	Username	Problem	Language	Result	Execution time	Memory
782728		math_rabbit_1028	즐거운 채소 기르기 (JOI14_growing)	C++14	45 / 100	203 ms	17748 KiB

growing

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
ll n, arr[303030];
vector<ll> com;

ll tree[1010101];
ll ans, cnt1[303030], cnt2[303030];

void init(ll v, ll st, ll ed) {
    if (st == ed) {
        tree[v] = 0;
        return;
    }
    ll mid = (st + ed) / 2;
    init(2 * v, st, mid);
    init(2 * v + 1, mid + 1, ed);
    tree[v] = tree[2 * v] + tree[2 * v + 1];
}

void update(ll v, ll st, ll ed, ll idx, ll val) {
    if (st == idx && ed == idx) {
        tree[v] += val;
        return;
    }
    if (idx < st || idx > ed) return;
    ll mid = (st + ed) / 2;
    update(2 * v, st, mid, idx, val);
    update(2 * v + 1, mid + 1, ed, idx, val);
    tree[v] = tree[2 * v] + tree[2 * v + 1];
}

ll get(ll v, ll st, ll ed, ll lt, ll rt) {
    if (st > rt || ed < lt) return 0;
    if (lt <= st && ed <= rt) return tree[v];
    ll mid = (st + ed) / 2;
    return get(2 * v, st, mid, lt, rt) + get(2 * v + 1, mid + 1, ed, lt, rt);
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cin >> n;
    for (ll i = 1; i <= n; i++) cin >> arr[i];
    for (ll i = 1; i <= n; i++) com.push_back(arr[i]);
    sort(com.begin(), com.end());
    com.erase(unique(com.begin(), com.end()), com.end());
    for (ll i = 1; i <= n; i++) {
        arr[i] = lower_bound(com.begin(), com.end(), arr[i]) - com.begin();
    }

    init(1, 0, com.size() - 1);
    for (ll i = 1; i <= n; i++) {
        cnt1[i] = get(1, 0, com.size() - 1, arr[i] + 1, com.size() - 1);
        update(1, 0, com.size() - 1, arr[i], 1);
    }

    init(1, 0, com.size() - 1);
    for (ll i = n; i >= 1; i--) {
        cnt2[i] = get(1, 0, com.size() - 1, arr[i] + 1, com.size() - 1);
        update(1, 0, com.size() - 1, arr[i], 1);
    }

    for (ll i = 1; i <= n; i++) {
        ans += min(cnt1[i], cnt2[i]);
    }

    cout << ans << "\n";

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 15 / 15
• Subtask 4: 0 / 55