Submission #1197867

#	Time	Username	Problem	Language	Result	Execution time	Memory
1197867		og_matveychick1	Cultivation (JOI17_cultivation)	C++20	80 / 100	2075 ms	4924 KiB

cultivation

#include "bits/stdc++.h"

using namespace std;

typedef long long ll;
typedef pair<ll, ll> pll;
typedef vector<ll> vll;


const ll N = 305;

ll n, r, c, x[N], y[N], ans = 1e18, _x[N], _y[N], ps[N], pL[N][N], pR[N][N], pmx[N][N], itl[N], itr[N];

void prec() {
    for (ll gl = 0; gl < n; gl++) {
        for (ll gr = gl; gr < n; gr++) {
            vector<ll> a;
            for (ll i = gl; i <= gr; i++) a.push_back(y[i]);
            sort(a.begin(), a.end());
            pL[gl][gr] = a[0];
            pR[gl][gr] = c - 1 - a[gr - gl];
            for (ll i = 1; i < a.size(); i++) pmx[gl][gr] = max(pmx[gl][gr], a[i] - a[i - 1] - 1);
        }
    }
}

signed main() {
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    cin >> r >> c >> n;
    for (ll i = 0; i < n; i++) cin >> x[i] >> y[i], x[i]--, y[i]--;
    iota(ps, ps + n, 0);
    sort(ps, ps + n, [&](ll a, ll b) { return x[a] < x[b]; });
    for (ll i = 0; i < n; i++) _x[i] = x[ps[i]], _y[i] = y[ps[i]];
    for (ll i = 0; i < n; i++) swap(x[i], _x[i]), swap(y[i], _y[i]);

    prec();
    for (ll up = 0; up < n; up++) { // n
        vll cup;
        for (ll i = 0; i < n; i++) {
            cup.push_back(r - 1 - x[i]);
            for (ll j = i; j < n; j++) {
                cup.push_back(max(0ll, abs(x[i] - x[j]) - 1 - x[up]));
            }
        }
        sort(cup.begin(), cup.end());
        cup.resize(unique(cup.begin(), cup.end()) - cup.begin());
        ll il = 0, ir = -1;
        vector<array<ll, 2>> s;
        multiset<ll> sL, sR, smx;
        ll ce = 0;
        for (ll i = 0; i < n; i++) { // n^3
            if (x[i] + cup[0] + 1 < r) {
                while (il < n && x[il] + cup[0] < x[i] + cup[0] + 1) il++;
                while (ir + 1 < n && x[ir + 1] - x[up] <= x[i] + cup[0] + 1) ir++;
                itl[i] = il;
                itr[i] = ir;
                if (ir < il) ce++;
                else {
                    sL.insert(pL[il][ir]);
                    sR.insert(pR[il][ir]);
                    smx.insert(pmx[il][ir]);
                }
                ll pr = ir;
                while (pr + 1 < n) {
                    pr++;
                    s.push_back({(x[pr] - x[up]) - (x[i] + cup[0] + 1), i});
                }
                s.push_back({r - (x[i] + cup[0] + 1), i});
            }
        }
        il = 0, ir = -1;
        while (il < n && x[il] + cup[0] < 0) il++;
        while (ir + 1 < n && x[ir + 1] - x[up] <= 0) ir++;
        sort(s.begin(), s.end());
        ll it = 0;
        ans = min(ans, (ce ? (ll) 1e18 : max(max(pmx[il][ir], (smx.size() ? *--smx.end() : 0ll)),
                                             max(pL[il][ir], (sL.size() ? *--sL.end() : 0ll)) +
                                             max(pR[il][ir], (sR.size() ? *--sR.end() : 0)))) +
                       cup[0] + x[up]);
        for (ll dn = 1; dn < cup.size(); dn++) {
            while (it < s.size() && s[it][0] <= cup[dn]) {
                ll i = s[it][1];
                if (itr[i] < itl[i]) ce--;
                else {
                    sL.erase(sL.find(pL[itl[i]][itr[i]]));
                    sR.erase(sR.find(pR[itl[i]][itr[i]]));
                    smx.erase(smx.find(pmx[itl[i]][itr[i]]));
                }
                itr[i]++;
                if (itr[i] != n) {
                    sL.insert(pL[itl[i]][itr[i]]);
                    sR.insert(pR[itl[i]][itr[i]]);
                    smx.insert(pmx[itl[i]][itr[i]]);
                }
                it++;
            }
            while (il < n && x[il] + cup[0] < 0) il++;
            while (ir + 1 < n && x[ir + 1] - x[up] <= 0) ir++;
            ans = min(ans, (ce ? (ll) 1e18 : max(max(pmx[il][ir], (smx.size() ? *--smx.end() : 0ll)),
                                                 max(pL[il][ir], (sL.size() ? *--sL.end() : 0ll)) +
                                                 max(pR[il][ir], (sR.size() ? *--sR.end() : 0)))) +
                           cup[dn] + x[up]);
        }
//        for (ll dn = 0; dn < cup.size(); dn++) { // n^3
//            long long mx = 0, L = 0, R = 0;
//            vector<ll> cp{0, r - 1};
//            for (ll i = 0; i < n; i++) { // n^4
//                if (x[i] + cup[dn] < r - 1) cp.push_back(x[i] + cup[dn] + 1);
//            }
//            sort(cp.begin(), cp.end());
//            cp.resize(unique(cp.begin(), cp.end()) - cp.begin());
//            ll itl = 0, itr = -1;
//            for (auto p: cp) { // n^4
//                while (itl < n && x[itl] + cup[dn] < p) itl++;
//                while (itr + 1 < n && x[itr + 1] - x[up] <= p) itr++;
//                if (itl > itr) {
//                    mx = 1e18;
//                    break;
//                }
//                mx = max(mx, pmx[itl][itr]);
//                L = max(L, pL[itl][itr]);
//                R = max(R, pR[itl][itr]);
//            }
//            ans = min(ans, max(mx, L + R) + cup[dn] + x[up]);
//        }
    }
    cout << ans;
}

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