Submission #1071908

#	Time	Username	Problem	Language	Result	Execution time	Memory
1071908		mickey080929	Cultivation (JOI17_cultivation)	C++17	80 / 100	2048 ms	4864 KiB

cultivation

#include <bits/stdc++.h>
 
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("Ofast")
 
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> pll;
 
const ll inf = 2e18;
 
ll R, C;
ll N;
 
ll mxl[310][310], mxr[310][310], mxsum[310][310];
 
ll solve(vector<pll> &p, ll H) {
    vector<pll> upd;
    upd.reserve(N * 2);
    ll j = 0;
    for (ll i=0; i<N; i++) {
        while (j < N && p[j].first + H <= p[i].first) {
            upd.push_back({p[j].first + H, -p[j].second});
            j ++;
        }
        upd.push_back(p[i]);
    }
    while (j < N) {
        upd.push_back({p[j].first + H, -p[j].second});
        j ++;
    }
    vector<array<ll,4>> save;
    ll idx1 = 0, idx2 = -1;
    for (ll i=0; i<N*2; i++) {
        if (upd[i].second > 0) idx2 ++;
        else idx1 ++;
        if (i + 1 != N*2 && upd[i].first == upd[i+1].first) continue;
        if (idx1 > idx2) {
            save.push_back({upd[i].first, inf, inf, inf});
            continue;
        }
        save.push_back({upd[i].first, mxsum[idx1][idx2], mxl[idx1][idx2], mxr[idx1][idx2]});
    }
    ll ans = inf;
    deque<ll> dq[3];
    for (ll i=(ll)save.size()-1; i>=0; i--) {
        for (ll j=0; j<3; j++) {
            while (!dq[j].empty() && save[dq[j].back()][j+1] <= save[i][j+1]) {
                dq[j].pop_back();
            }
            while (!dq[j].empty() && save[dq[j].front()][0] > save[i][0] + R - 1) {
                dq[j].pop_front();
            }
            dq[j].push_back(i);
        }
        ans = min(ans, max(save[dq[0].front()][1], save[dq[1].front()][2] + save[dq[2].front()][3]));
    }
    return ans;
}
 
int main() {
    ios_base :: sync_with_stdio(false); cin.tie(NULL);
    cin >> R >> C;
    cin >> N;
    vector<pll> p(N);
    for (ll i=0; i<N; i++) {
        cin >> p[i].first >> p[i].second;
    }
    sort(p.begin(), p.end());
    for (ll i=0; i<N; i++) {
        vector<ll> cur;
        for (ll j=i; j<N; j++) {
            if (cur.empty() || cur.back() < p[j].second) {
                cur.push_back(p[j].second);
            }
            else {
                for (ll k=0; k<cur.size(); k++) {
                    if (cur[k] >= p[j].second) {
                        cur.insert(cur.begin() + k, p[j].second);
                        break;
                    }
                }
            }
            ll l = cur[0] - 1, r = C - cur.back();
            ll sum = l + r;
            for (ll k=0; k+1<cur.size(); k++) {
                sum = max(sum, cur[k+1] - cur[k] - 1);
            }
            mxl[i][j] = l; mxr[i][j] = r;
            mxsum[i][j] = sum;
        }
    }
    vector<ll> cand, U, D;
    for (ll i=0; i<N; i++) {
        U.push_back(p[i].first - 1);
        D.push_back(R - p[i].first);
        for (ll j=i+1; j<N; j++) {
            cand.push_back(abs(p[i].first - p[j].first));
        }
    }
    for (auto &u : U) {
        for (auto &d : D) {
            cand.push_back(u + d + 1);
        }
    }
    sort(cand.begin(), cand.end());
    cand.erase(unique(cand.begin(), cand.end()), cand.end());
    ll ans = inf;
    for (auto &H : cand) {
        if (H == 0) continue;
        ans = min(ans, H - 1 + solve(p, H));
    }
    cout << ans << '\n';
}

Compilation message (stderr)

cultivation.cpp: In function 'int main()':
cultivation.cpp:79:31: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   79 |                 for (ll k=0; k<cur.size(); k++) {
      |                              ~^~~~~~~~~~~
cultivation.cpp:88:29: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   88 |             for (ll k=0; k+1<cur.size(); k++) {
      |                          ~~~^~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 15 / 15
• Subtask 4: 30 / 30
• Subtask 5: 20 / 20
• Subtask 6: 0 / 20