Submission #1181682

#	Time	Username	Problem	Language	Result	Execution time	Memory
1181682		SmuggingSpun	Room Temperature (JOI24_ho_t1)	C++20	100 / 100	656 ms	55240 KiB

Main

#include<bits/stdc++.h>
#define taskname "A"
using namespace std;
template<class T>void minimize(T& a, T b){
    if(a > b){
        a = b;
    }
}
template<class T>void maximize(T& a, T b){
    if(a < b){
        a = b;
    }
}
const int lim = 5e5 + 5;
int n, t, a[lim];
namespace sub1{
    void solve(){
        int d = abs(a[1] % t - a[2] % t);
        minimize(d, t - d);
        cout << ((d + 1) >> 1);
    }
}
namespace sub23{
    void solve(){
        if(t == 1){
            return void(cout << 0);
        }
        for(int i = 2; i <= n; i++){
            if((a[i] & 1) != (a[1] & 1)){
                return void(cout << 1);
            }
        }
        cout << 0;
    }
}
namespace sub4{
    void solve(){
        int ans = t;
        for(int i = 0; i < t; i++){
            int candidate = 0;
            for(int j = 1; j <= n; j++){
                int d = abs(a[j] - i) % t;
                maximize(candidate, min(d, t - d));
            }
            minimize(ans, candidate);
        }
        cout << ans;
    }
}
namespace sub5{
    struct Event{
        int time, type, value;
        Event(){}
        Event(int _time, int _type, int _value) : time(_time), type(_type), value(_value) {}
        bool operator <(const Event& other){
            return this->time < other.time || (this->time == other.time && this->type > other.type);
        }
    };
    void solve(){
        vector<Event>event;
        vector<multiset<int>>S(2);
        for(int i = 1; i <= n; i++){
            int mod = a[i] % t, p = (mod - (t >> 1) + t) % t;
            event.emplace_back(p, 1, (t >> 1) + p);
            if(p > mod){
                event.emplace_back(0, 1, mod);
                event.emplace_back(mod + 1, -1, mod);
            }
            else{
                event.emplace_back(mod + 1, -1, (t >> 1) + p);
            }
            event.emplace_back(mod, 2, -mod);
            if((p = (mod + (t >> 1)) % t) < mod){
                event.emplace_back(0, 2, t - mod);
                event.emplace_back(p + 1, -2, t - mod);
            }
            else{
                event.emplace_back(p + 1, -2, -mod);
            }
        }
        sort(event.begin(), event.end());
        event.emplace_back(t, 0, 0);
        int ans = t;
        for(int i = 0; event[i].time < t; i++){
            if(event[i].type > 0){
                S[event[i].type - 1].insert(event[i].value);
            }
            else{
                S[-event[i].type - 1].erase(S[-event[i].type - 1].find(event[i].value));
            }
            if(event[i].time != event[i + 1].time){
                if(S[0].empty() && S[1].empty()){
                    minimize(ans, 0);
                }
                else if(S[0].empty()){
                    minimize(ans, max(0, *S[1].rbegin() + event[i].time));
                }
                else if(S[1].empty()){
                    minimize(ans, max(0, *S[0].rbegin() - event[i + 1].time + 1));
                }
                else{
                    int decrease = *S[0].rbegin() - event[i].time, increase = *S[1].rbegin() + event[i].time;
                    if(decrease > increase){
                        int opt_time = min(event[i + 1].time - 1, event[i].time + ((decrease - increase) >> 1));
                        minimize(ans, max(*S[0].rbegin() - opt_time, *S[1].rbegin() + opt_time));
                    }
                    else{
                        minimize(ans, increase);
                    }
                }
                minimize(ans, max(S[0].empty() ? 0 : *S[0].rbegin() - event[i].time, S[1].empty() ? 0 : *S[1].rbegin() + event[i].time));
            }
        }
        cout << ans;
    }
}
int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	if(fopen(taskname".inp", "r")){
		freopen(taskname".inp", "r", stdin);
	}
    cin >> n >> t;
    for(int i = 1; i <= n; i++){
        cin >> a[i];
    }
    if(n == 2){
        sub1::solve();
    }
    else if(t <= 2){
        sub23::solve();
    }
    else if(max(n, t) <= 3000){
        sub4::solve();
    }
    else{
        sub5::solve();
    }
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:120:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  120 |                 freopen(taskname".inp", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 5 / 5
• Subtask 3: 30 / 30
• Subtask 4: 35 / 35
• Subtask 5: 15 / 15