Submission #568883

#	Time	Username	Problem	Language	Result	Execution time	Memory
568883		shrimb	Street Lamps (APIO19_street_lamps)	C++17	40 / 100	119 ms	13164 KiB

street_lamps

#pragma GCC optimize ("Ofast")
#pragma GCC target ("avx,avx2,fma")

#include"bits/stdc++.h"
using namespace std;

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;

template<class x>
using ordered_set = tree<x, null_type,less<x>, rb_tree_tag,tree_order_statistics_node_update>;

#define int long long
#define endl '\n'
#define mod 1000000007
//\
#define mod 1686876991

const int maxn = 300005;

int pre[maxn], A[maxn];

int Sparse[maxn][20];

int Query (int l, int r) {
    int d = (r - l + 1);
    int lg = log2(d);
    return max(Sparse[l][lg], Sparse[r - (1 << lg) + 1][lg]);
}

signed main () {
    cin.tie(0)->sync_with_stdio(0);

    int n, q;
    cin >> n >> q;
    string s;
    cin >> s;
    if (n <= 100 and q <= 100) {
        vector<string> v;
        while (q--) {
            v.push_back(s);
            string t;
            cin >> t;
            if (t == "query") {
                int l, r, ans = 0;
                cin >> l >> r;
                for (auto i : v) {
                    bool good = 1;
                    for (int j = l - 1 ; j < r - 1 ; j++) {
                        if (i[j] == '0') good = 0;
                    }
                    ans += good;
                }
                cout << ans << endl;
            } else {
                int i;
                cin >> i;
                s[i-1] = '0'+((s[i-1]-'0')^1);
            }
        }
        return 0;
    }

    array<int, 3> Q[q];
    bool ST2 = 1;

    for (int i = 0 ; i < q ; i++) {
        string t;
        cin >> t >> Q[i][1];
        Q[i][0] = (t == "query");
        if (Q[i][0]) cin >> Q[i][2];
        else Q[i][2] = 0;
        if (Q[i][0] and Q[i][2] - Q[i][1] != 1) ST2 = 0;
        Q[i][2]-=2, Q[i][1]--;
    }

    if (ST2) {
        memset(pre, -1, sizeof pre);
        for (int i = 0 ; i < n ; i++) if (s[i] == '1') pre[i] = 0;
        int ct = 0;
        for (auto [t, l, r] : Q) {
            ct++;
            if (t) {
                int sm = A[l];
                if (pre[l] != -1) sm += ct - pre[l];
                cout << sm << endl;
            } else {
                if (pre[l] == -1) pre[l] = ct;
                else {
                    A[l] += ct - pre[l];
                    pre[l] = -1;
                }
            }
        }
        return 0;
    }

    for (int i = 0 ; i < n ; i++) {
        if (s[i] == '1') Sparse[i][0] = 0;
        else Sparse[i][0] = INT_MAX;
    }
    for (int i = 0 ; i < q ; i++) {
        if (!Q[i][0]) Sparse[Q[i][1]][0] = i + 1;
    }
    for (int j = 1 ; j < 20 ; j++) {
        for (int i = 0 ; i < n and i + (1 << j) <= n ; i++) Sparse[i][j] = max(Sparse[i][j - 1], Sparse[i + (1 << j - 1)][j-1]);
    }
    for (int i = 0 ; i < q ; i++) {
        if (Q[i][0]) {
            cout << max(0ll, Query(Q[i][1], Q[i][2]) - i) << endl;
        }
    }
}

Compilation message (stderr)

street_lamps.cpp:17:1: warning: multi-line comment [-Wcomment]
   17 | //\
      | ^
street_lamps.cpp: In function 'int main()':
street_lamps.cpp:107:117: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
  107 |         for (int i = 0 ; i < n and i + (1 << j) <= n ; i++) Sparse[i][j] = max(Sparse[i][j - 1], Sparse[i + (1 << j - 1)][j-1]);
      |                                                                                                                   ~~^~~

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