Submission #1057416

#	Time	Username	Problem	Language	Result	Execution time	Memory
1057416		Mr_Husanboy	Bouquet (EGOI24_bouquet)	C++17	100 / 100	61 ms	16260 KiB

Main

//#pragma GCC optimize("Ofast,O3")
//#pragma GCC target("avx,avx2")
#include <bits/stdc++.h>
using namespace std;



#ifdef LOCAL
#include "debugger.cpp"
#else
#define debug(...)
#endif
template<class T>
int len(T &a){
    return a.size();
}

using ll = long long;
using pii = pair<int,int>;
#define all(a) (a).begin(), (a).end()
#define ff first
#define ss second
string fileio = "";

mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
const int MOD = 1e9 + 7;
const int inf = 1e9;
const ll infl = 1e18;
const int maxn = 1e5 + 1;





void yesno(bool ok){
    cout << (ok ? "Yes\n" : "No\n");
}

struct SegmentTree{
    int n;
    vector<int> t;
    SegmentTree (int n) : n(n), t(2 * n){}
    SegmentTree () {}

    int merge(int a, int b){
        return max(a, b);
    }

    void upd(int i, int val){
        i += n;
        t[i] = val;
        for(i /= 2; i > 0; i /= 2){
            t[i] = merge(t[i * 2], t[i * 2 + 1]);
        }
    }

    int get(int l, int r){
        l += n; r += n;
        int res = 0;
        while(l <= r){
            if(l & 1){
                res = merge(res, t[l ++]);
            }
            if(!(r & 1)){
                res = merge(res, t[r --]);
            }
            l /= 2; r /= 2;
        }
        return res;
    }
};      


void solve(){
    int n; cin >> n;
    vector<int> l(n), r(n);
    for(int i = 0; i< n; i ++){
        cin >> l[i] >> r[i];
    }



    SegmentTree t(n);

    vector<vector<pair<int,int>>> close(n);
    int mx = 0;
    for(int i = 0; i < n; i ++){
        int res = t.get(0, i - l[i] - 1) + 1;
        mx = max(mx, res);
        if(i + r[i] < n){
            close[i + r[i]].push_back({i, res});
        }
        for(auto [j, val] : close[i]){
            t.upd(j, val);
        }
    }
    cout << mx;
}

int main(){
    ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
    auto start = chrono::high_resolution_clock::now();
    #ifndef LOCAL
    if(fileio.size()){
        freopen((fileio + ".in").c_str(), "r", stdin);
        freopen((fileio + ".out").c_str(), "w", stdout);
    }
    #endif
    int testcases = 1;
    #ifdef Tests
    cin >> testcases;
    #endif
    while(testcases --){
        solve();
        if(testcases) cout << '\n';
        #ifdef LOCAL
        else cout << '\n';
        cout << "_________________________" << endl;
        #endif
    }
    #ifdef LOCAL
    auto duration = chrono::duration_cast<chrono::microseconds>(chrono::high_resolution_clock::now() - start);
    
    cout << "time: " << (double)duration.count()/1000.0 << " milliseconds" << endl;
    #endif
    return 0;
}       

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:102:10: warning: variable 'start' set but not used [-Wunused-but-set-variable]
  102 |     auto start = chrono::high_resolution_clock::now();
      |          ^~~~~
Main.cpp:105:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  105 |         freopen((fileio + ".in").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:106:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  106 |         freopen((fileio + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 16 / 16
• Subtask 3: 28 / 28
• Subtask 4: 18 / 18
• Subtask 5: 30 / 30