Submission #724049

#	Time	Username	Problem	Language	Result	Execution time	Memory
724049		sysia	Road Construction (JOI21_road_construction)	C++17	6 / 100	10080 ms	188068 KiB

road_construction

//Sylwia Sapkowska
#include <bits/stdc++.h>
#pragma GCC optimize("O3", "unroll-loops")
using namespace std;

void __print(int x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << "'" << x << "'";}
void __print(const char *x) {cerr << '"' << x << '"';}
void __print(const string &x) {cerr << '"' << x << '"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ", "; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? ", " : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifdef LOCAL
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

struct Tree {
	vector<int> s;
    Tree(){}
	Tree(int n) : s(n) {}
    void fit(int n){
        s.assign(n, 0);
    }
	void update(int pos) { // a[pos] += dif
		for (; pos < (int)s.size(); pos |= pos + 1) s[pos]++;
	}
	int query(int pos) { // sum of values in [0, pos)
		int res = 0;
		for (; pos > 0; pos &= pos - 1) res += s[pos-1];
		return res;
	}
	int query(int l, int r){
        return query(r+1) - query(l);
    }
};

#define int long long
typedef pair<int, int> T;
const int oo2 = 1e9+7;

void solve(){
    int n, k; cin >> n >> k;
    vector<T>p, p2(n);
    for (auto &[x, y]: p2) {
        cin >> x >> y;
        p.emplace_back(x+y, y-x);
    }
    vector<tuple<int, int, int8_t>>sweep;
    vector<int>s;
    Tree t;
    auto check = [&](int m){
        // debug(p);
        sweep.clear();
        s.clear();
        for (auto [x, y]: p){
            sweep.emplace_back(y-m, x, -1);
            sweep.emplace_back(y+m, x, +1);
            sweep.emplace_back(y, x, 0);
            s.emplace_back(x-m);
            s.emplace_back(x);
            s.emplace_back(x+m);
        }
        stable_sort(s.begin(), s.end());
        s.erase(unique(s.begin(), s.end()), s.end());
        int M = (int)s.size();
        t.fit(M+1);
        auto get = [&](int x)->int {
            return lower_bound(s.begin(), s.end(), x) - s.begin();
        };
        stable_sort(sweep.begin(), sweep.end());
        int all = 0;
        for (auto [y, x, what]: sweep){
            if (what == 0){
                t.update(get(x));
            } else {
                all += what * t.query(get(x-m), get(x+m));
            }
        }
        all -= n;
        all/=2;
        debug(m, all);
        return (all >= k);
    };
    int l = 1, r = oo2 * 2;
    int d = oo2 * 2;
    while (r >= l){
        int m = (l+r)/2;
        if (check(m)){
            d = m;
            r = m-1;
        } else l = m+1;
    }
    debug(d);
    map<T, vector<int32_t>>cnt;
    for (int i = 0; i<n; i++){
        cnt[{p2[i].first/d, p2[i].second/d}].emplace_back(i);
    }
    vector<int>X = {-1, -1, -1, 0, 0, 0, 1, 1, 1};
    vector<int>Y = {-1, 0, 1, -1, 0, 1, -1, 0, 1};
    vector<int>ret;
    for (auto &[coord, vec]: cnt){
        for (auto i: vec){
            for (int rep = 0; rep < 9; rep++){
                T now = {coord.first + X[rep], coord.second + Y[rep]};
                for (auto &j: cnt[now]){
                    if (i <= j) continue;
                    int x = abs(p2[i].first - p2[j].first) + abs(p2[i].second - p2[j].second);
                    if (x < d || (x == d && (int)ret.size() < k)) ret.emplace_back(x);
                }
            }
        }
    }
    stable_sort(ret.begin(), ret.end());
    for (int i = 0; i<k; i++) cout << ret[i] << "\n";
}

int32_t main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int t = 1;
    //cin >> t;
    while (t--) solve();

    return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 6 / 6
• Subtask 3: 0 / 7
• Subtask 4: 0 / 20
• Subtask 5: 0 / 27
• Subtask 6: 0 / 35