Submission #882183

#	Time	Username	Problem	Language	Result	Execution time	Memory
882183		Mr_Husanboy	Weighting stones (IZhO11_stones)	C++17	100 / 100	42 ms	7716 KiB

stones

#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 mt(time(nullptr));
const int mod = 1e9 + 7;
const int inf = 1e9;
const ll infl = 1e18;
const int maxn = 1e5 + 1;




struct SegmentTree{

    //To change
    struct Node{
        //defaults
        int mn = 0, mx = 0;
        int add = 0;
        bool marked = false;
        void apply(int x){
            mx += x; mn += x;
            add += x;
            marked = true;
        }
    };

    void push(int x){
        if(t[x].marked){
            t[x << 1].apply(t[x].add);
            t[x << 1 | 1].apply(t[x].add);
            t[x].add = 0; t[x].marked = false;
        }
    }

    Node merge(Node a, Node b){
        return {min(a.mn, b.mn), max(a.mx, b.mx), 0, false};
    }

    Node neutral = {inf, -inf, 0, false};
    vector<Node> t;
    int n;

    //construction

    void init(int _n){
        n = _n;
        t.resize(4 * n);
    }


    void upd(int x, int lx, int rx, int l, int r, int val){
        if(rx < l || r < lx) return;
        if(l <= lx && rx <= r){
            t[x].apply(val); return;
        }
        push(x);
        int mx = (lx + rx) >> 1;
        upd(x << 1, lx, mx, l, r, val);
        upd(x << 1 | 1, mx + 1, rx, l, r, val);
        t[x] = merge(t[x << 1], t[x << 1 | 1]);
    }

    Node get(int x, int lx, int rx, int l, int r){
        if(rx < l || r < lx){
            return neutral;
        }
        if(l <= lx && rx <= r){
            return t[x];
        }
        push(x);
        int mx = (lx + rx) >> 1;
        return merge(get(x << 1, lx, mx, l, r), get(x << 1 | 1, mx + 1, rx, l, r));
    }

    // lessen

    void upd(int l, int r, int val){
        upd(1, 0, n - 1, l, r, val);
    }

    Node get(int l, int r){
        return get(1, 0, n - 1, l, r);
    }
};


void solve(){
    int n;
    cin >> n;

    SegmentTree t;
    t.init(n);

    for(int _ = 0; _ < n; _ ++){
        int l, r; cin >> l >> r;
        l --; 
        t.upd(0, l, (r == 1 ? -1 : 1));
        auto k = t.get(0, n - 1);
        cout << (k.mx <= 0 ? ">" : k.mn >= 0 ? "<" : "?") << '\n';
    }
}

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();
        cout << '\n';
        #ifdef LOCAL
        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)

stones.cpp: In function 'int main()':
stones.cpp:126:10: warning: variable 'start' set but not used [-Wunused-but-set-variable]
  126 |     auto start = chrono::high_resolution_clock::now();
      |          ^~~~~
stones.cpp:129:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  129 |         freopen((fileio + ".in").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
stones.cpp:130:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  130 |         freopen((fileio + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100