Submission #655094

#	Time	Username	Problem	Language	Result	Execution time	Memory
655094		DeMen100ns	Street Lamps (APIO19_street_lamps)	C++17	20 / 100	2750 ms	48532 KiB

street_lamps

/*
Author : DeMen100ns (a.k.a Vo Khac Trieu)
School : VNU-HCM High school for the Gifted
fuck you adhoc
*/

#include <bits/stdc++.h>

using namespace std;

const int N = 3e5 + 5;
const long long INF = 1e18 + 7;
const int MAXA = 1e9;
const int B = sqrt(N) + 5;

int n, q;
string s;

int seg[4 * N], L[N], R[N];
array<int, 3> qu[N];
vector <int> p[N];

void upd(int id, int l, int r, int pos){
    if (l == r){
        seg[id] ^= 1;
        return;
    }

    int mid = (l + r) >> 1;
    if (pos <= mid) upd(id << 1, l, mid, pos);
    else upd(id << 1 | 1, mid + 1, r, pos);
    
    seg[id] = seg[id << 1] + seg[id << 1 | 1];
}

int get(int id, int l, int r, int u, int v){
    if (l > v || r < u) return 0;

    if (l >= u && r <= v) return seg[id];

    int mid = (l + r) >> 1;
    int v1 = get(id << 1, l, mid, u, v);
    int v2 = get(id << 1 | 1, mid + 1, r, u, v);

    return v1 + v2;
}

void subtask3(){
    s = " " + s;

    for(int i = 1; i <= q; ++i){
        string type;
        cin >> type;
        if (type == "query") {
            int l, r; cin >> l >> r;

            qu[i] = {0, l, r - 1};
        }
        else {
            int p; cin >> p;
            qu[i] = {1, p, -1};
        }

        L[i] = -1, R[i] = q + 1;
    }

    for(bool run = true; run;){
        run = false;
        for(int i = 1; i <= q; ++i){
            if (qu[i][0] == 0 && L[i] + 1 < R[i]){
                p[(L[i] + R[i]) >> 1].push_back(i);
                run = true;
            }
        }
        memset(seg, 0, sizeof seg);
        for(int i = 1; i <= n; ++i){
            if (s[i] == '1') upd(1, 1, n, i);
        }
        for(int id : p[0]){
            if (get(1, 1, n, qu[id][1], qu[id][2]) == (qu[id][2] - qu[id][1] + 1)){
                R[id] = 0;
            } else L[id] = 0;
        }
        p[0].clear();

        for(int i = 1; i <= q; ++i){
            if (qu[i][0] == 1){
                upd(1, 1, n, qu[i][1]);
            }
            for(int id : p[i]){
                if (get(1, 1, n, qu[id][1], qu[id][2]) == (qu[id][2] - qu[id][1] + 1)){
                    R[id] = i;
                } else L[id] = i;
            }
            p[i].clear();
        }
    }

    for(int i = 1; i <= q; ++i){
        if (qu[i][0] == 0){
            cout << max(0, i - R[i]) << endl;
        }
    }
}

void solve()
{
    cin >> n >> q;
    cin >> s;
    
    subtask3();
}

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

    // freopen("codeforces.inp","r",stdin);
    // freopen("codeforces.out","w",stdout);

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

• Subtask 1: 0 / 20
• Subtask 2: 0 / 20
• Subtask 3: 20 / 20
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20