Submission #1282334

#	Time	Username	Problem	Language	Result	Execution time	Memory
1282334		trungcan	Road Construction (JOI21_road_construction)	C++17	100 / 100	1137 ms	8276 KiB

road_construction

#include <bits/stdc++.h>
#define ll long long
#define pll pair<ll, ll>
#define fi first
#define se second
using namespace std;
const int N = 250005;
int n, k;
ll num;
pll a[N];
vector<ll> ans;
bool check(ll x){
    multiset<ll> s;
    int j = 1, cnt = 0;
    for (int i = 1; i <= n; ++i){
        while (a[j].fi < a[i].fi - x){
            s.erase(s.find(a[j].se));
            ++j;
        }
        for (multiset<ll>::iterator it = s.lower_bound(a[i].se - x); it != s.end() && *it <= a[i].se + x; ++it)
            if (++cnt >= k) return 1;
        s.insert(a[i].se);
    }
    return 0;
}
int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    if (fopen("test.inp", "r")){
        freopen("test.inp", "r", stdin);
        freopen("test.out", "w", stdout);
    }
    cin >> n >> k;
    for (int i = 1, u, v; i <= n; ++i){
        cin >> u >> v;
        a[i].fi = u + v; a[i].se = u - v;
    }
    sort(a + 1, a + n + 1);
    ll l = 1, r = 4e9;
    while (l <= r){
        ll mid = l + ((r - l) >> 1);
        if (check(mid)){
            num = mid;
            r = mid - 1;
        } else
            l = mid + 1;
    }
    --num;
    multiset<pll> s;
    int j = 1;
    for (int i = 1; i <= n; ++i){
        while (j < i && a[j].fi < a[i].fi - num){
            s.erase(s.find(make_pair(a[j].se, a[j].fi)));
            ++j;
        }
        for (multiset<pll>::iterator it = s.lower_bound(make_pair(a[i].se - num, -(ll)4e9)); it != s.end() && (*it).fi <= a[i].se + num; ++it)
            ans.push_back(max(abs(a[i].se - (*it).fi), abs(a[i].fi - (*it).se)));
        s.insert(make_pair(a[i].se, a[i].fi));
    }
    sort(ans.begin(), ans.end());
    for (ll x: ans) cout << x << "\n";
    k -= (int)ans.size();
    while (k--)
        cout << num + 1 << "\n";
}

Compilation message (stderr)

road_construction.cpp: In function 'int main()':
road_construction.cpp:29:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   29 |         freopen("test.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
road_construction.cpp:30:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |         freopen("test.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 6 / 6
• Subtask 3: 7 / 7
• Subtask 4: 20 / 20
• Subtask 5: 27 / 27
• Subtask 6: 35 / 35