Submission #952378

#	Time	Username	Problem	Language	Result	Execution time	Memory
952378		GrindMachine	IOI Fever (JOI21_fever)	C++17	6 / 100	1 ms	460 KiB

fever

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

vector<ll> dx = {1,-1,0,0};
vector<ll> dy = {0,0,1,-1};

void solve(int test_case)
{
    ll n; cin >> n;
    vector<pll> a(n+5);
    rep1(i,n) cin >> a[i].ff >> a[i].ss;

    vector<bool> vis(n+5);
    ll ans = 0;

    rep(dir,4){
        queue<array<ll,3>> q;
        fill(all(vis),0);
        q.push({1,0,dir});
        vis[1] = 1;

        while(!q.empty()){
            auto [i,t,d1] = q.front();
            q.pop();
            auto [x1,y1] = a[i];

            rep1(j,n){
                if(vis[j]) conts;
                auto [x2,y2] = a[j];
                // x1+dx[d1]*k = x2+dx[d2]*k
                // y1+dy[d1]*k = y2+dy[d2]*k
                
                rep(d2,4){
                    if(dx[d1] == dx[d2] or dy[d1] == dy[d2]) conts;
                    ll k1 = 2*(x2-x1)/(dx[d1]-dx[d2]);
                    ll k2 = 2*(y2-y1)/(dy[d1]-dy[d2]);
                    if(k1 == k2){
                        if(k1 > t){
                            q.push({j,k1,d2});
                            vis[j] = 1;
                        }
                    }
                }
            }
        }

        ll cnt = count(all(vis),1);
        amax(ans,cnt);
    }

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 8
• Subtask 3: 6 / 6
• Subtask 4: 0 / 6
• Subtask 5: 0 / 12
• Subtask 6: 0 / 32
• Subtask 7: 0 / 31