Submission #1118693

#	Time	Username	Problem	Language	Result	Execution time	Memory
1118693		Icelast	Advertisement 2 (JOI23_ho_t2)	C++17	100 / 100	502 ms	52440 KiB

Main

#include <iostream>
#include <bits/stdc++.h>
#define ll long long
using namespace std;
const ll maxn = 2*1e5+5, INF = 4e18+9;
struct people{
    ll x, e, id;
};
struct segment{
    ll l, r;
};
struct normalize{
    vector<ll> poi, pot;
    void add(ll x){
        poi.push_back(x);
    }
    void start(){
        sort(poi.begin(), poi.end());
        if(poi.size() > 0) pot.push_back(poi[0]);
        for(int i = 1; i < (int)poi.size(); i++){
            if(poi[i] != poi[i-1]){
                pot.push_back(poi[i]);
            }
        }
    }
    int encode(ll x){
        return lower_bound(pot.begin(), pot.end(), x) - pot.begin()+1;
    }
};
template <class T>
struct Fenwick {
    int n, log;
    vector<T> bit;

    Fenwick(int n) : n(n), log(32 - __builtin_clz(n + 1)), bit(n + 1, 0) {}

    void add(int i, T delta) {
        for (; i <= n; i += i & -i) {
            bit[i] += delta;
        }
    }

    T sum(int i) {
        T res = 0;
        for (; i > 0; i -= i & -i) {
            res += bit[i];
        }
        return res;
    }
    T sum(int l, int r) {
        return sum(r)-sum(l-1);
    }
    int kth(T k) {
        T sum = 0;
        int pos = 0;
        for (int l = log - 1; l >= 0; l--) {
            if (pos + (1 << l) <= n && sum + bit[pos + (1 << l)] <= k) {
                pos += 1 << l;
                sum += bit[pos];
            }
        }
        return pos;
    }
};
void solve(){
    int n;
    cin >> n;
    vector<people> a(n+1);
    for(int i = 1; i <= n; i++){
        cin >> a[i].x >> a[i].e;
        a[i].id = i;
    }
    sort(a.begin()+1, a.end(), [&](people a, people b){return a.e < b.e || (a.e == b.e && a.x < b.x);});
    vector<segment> s(1);
    normalize norm;
    for(int i = 1; i <= n; i++){
        s.push_back({a[i].x-a[i].e, a[i].x+a[i].e});
        norm.add(s[i].l);
        norm.add(s[i].r);
    }
    norm.start();
    for(int i = 1; i <= n; i++){
        s[i] = {norm.encode(s[i].l), norm.encode(s[i].r)};
    }
    int N = norm.pot.size();
    Fenwick<int> bit(N+1);
    sort(s.begin()+1, s.end(), [&](segment a, segment b){return a.l < b.l || (a.l == b.l && a.r > b.r);});
    int ans = 0;
    for(int i = 1; i <= n; i++){
        if(!bit.sum(s[i].r, N)){
            ans++;
        }
        bit.add(s[i].r, 1);
    }
    cout << ans;
}
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    solve();
}

• Subtask 1: 10 / 10
• Subtask 2: 23 / 23
• Subtask 3: 36 / 36
• Subtask 4: 31 / 31