Submission #1171183

#	Time	Username	Problem	Language	Result	Execution time	Memory
1171183		mmmmge1234	Cultivation (JOI17_cultivation)	C++20	60 / 100	2096 ms	15688 KiB

cultivation

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

#define st first
#define nd second

const int maxn = 300;

struct help{
        int mine,minw,mins;
};
help pcomp[maxn][maxn];

int main(){
        if(fopen("lighter.inp" , "r")){
                freopen("lighter.inp", "r", stdin);
                freopen("lighter.out", "w", stdout);
        }
        cin.tie(0)->sync_with_stdio(0);
        cout.tie(0)->sync_with_stdio(0);
        int r,c;
        cin >> r >> c;
        int n;
        cin >> n;
        vector<pair<int,int>>  vpii(n);
        for(int i = 0; i < n;i++){
                cin >> vpii[i].st >> vpii[i].nd;
                vpii[i].st--, vpii[i].nd--;
        }

        sort(vpii.begin(), vpii.end());

        for(int i = 0; i < n; i++){
                set<int> si;
                multiset<int> diff;
                for(int j = i; j < n; j++){
                        auto [it,trying] = si.insert(vpii[j].nd);
                        if(!trying){
                                pcomp[i][j].minw = *si.begin();
                                pcomp[i][j].mine = c - 1 - *si.rbegin();
                                if(!diff.empty())
                                        pcomp[i][j].mins = *diff.rbegin();
                                continue;
                        }
                        auto bef = it, aft = it;
                        aft++;

                        if(it != si.begin())
                                bef--;
                        if(it != si.begin() && aft != si.end()){
                                diff.erase(diff.find(*aft - *bef - 1));
                        }
                        if(it != si.begin()){
                                diff.insert(*it - *bef - 1);
                        }
                        if(aft != si.end()){
                                diff.insert(*aft - *it - 1);
                        }

                        pcomp[i][j].minw = *si.begin();
                        pcomp[i][j].mine = c - 1 - *si.rbegin();
                        if(!diff.empty()){
                                pcomp[i][j].mins = *diff.rbegin();
                        }
                }
        }

        int minn = INT_MAX, minso = INT_MAX, mins = 0;
        for(auto a : vpii)
                minn = min(minn,a.st), minso = min(minso, r - a.st - 1);
        for(int i = 0; i < vpii.size() - 1; i++){
                mins = max(mins, vpii[i + 1].st - vpii[i].st - 1);
        }

        set<pair<int,int >>  extra;

        set<int> extran,extras;
        extran.insert(0),extras.insert(0);
        for(int i = 0; i <n;i++){
                extran.emplace(vpii[i].st);
                extras.emplace((r - 1) - (vpii[i].st));
        }

        set<int> gap;
        gap.insert(0);
        gap.insert(mins);
        for(int i = 0; i < n;i++)
                for(int j = i + 2; j < n;j++){
                        gap.emplace((vpii[j].st) - (vpii[i].st));
                        gap.emplace(max(0,(vpii[j].st) - (vpii[i].st) - 1));
                }

        for(auto a : extran){
                for(auto b : extras){
                        if(a+b >= mins && a>= minn && b >= minso){
                                extra.emplace(a,b);
                        }
                }
        }
        for(auto a : extran){
                for(auto b : gap){
                        if(b>=a && b >= mins && a>=minn && b-a >=minso){
                                extra.emplace(a,b-a);
                        }
                }
        }
        for(auto a : extras){
                for(auto b : gap){
                        if(b>=a && b >= mins && b-a>=minn && a >= minso){
                                extra.emplace(b - a,a);
//                                cout << "'" << b - a << " " << a << "'" << '\n';
                        }
                }
        }
        long long minans = LLONG_MAX;
        for(auto a : extra){
                map<int, vector<int >>  mivi;
                for(int i = 0; i < n;i++){
                        int add = vpii[i].st - a.st,minus = vpii[i].st + 1 + a.nd;
                        add = max(add,0);
                        mivi[add].push_back(i + 1);
                        if(minus < r){
                                mivi[minus].push_back(-(i+1));
                        }
                }
                int minw = 0, mine = 0, minsum = 0;
                set<int> curin;
                for(auto &a : mivi){
                        for(auto b : a.nd){
                                if(b>0){
                                        curin.insert(b - 1);
                                }
                                else{
                                        curin.erase(-b - 1);
                                }
                        }
                        int sm = *curin.begin(), bg = *curin.rbegin();
                        assert((bg - sm + 1) == curin.size());
                        minw = max(minw, pcomp[sm][bg].minw);
                        mine = max(mine, pcomp[sm][bg].mine);
                        minsum = max(minsum, pcomp[sm][bg].mins);
//                        cout << minw << " " << mine << " " << minsum << '\n';
                }
                minans = min(minans, max((long long)minsum, (long long)mine + minw) + a.st + a.nd);
        }
        cout << minans << '\n';
}

Compilation message (stderr)

cultivation.cpp: In function 'int main()':
cultivation.cpp:16:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |                 freopen("lighter.inp", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
cultivation.cpp:17:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 |                 freopen("lighter.out", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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